Lore
In the sunlit shallows flanking the great barrier reefs of the island country of Lapita, the artisans of the coastal wharfs observed how the native manta rays, predatory barracudas, and river-dolphins cut through turbulent swells without being dragged down by oceanic counter-currents. During the early decades of the current industrial era, an ambitious artisan guild operating out of a tidewater settlement sought to harness these natural dynamics for newly reincarnated aquatic avatars who struggled to balance their heavy arcane gear against the relentless pull of the moon’s tidal surges. The crafting artisans captured preserved biological membranes shed by sentient reef-skimmers and integrated them with flexible, steam-treated baleen ribs harvested with fluid collectors.
These fins were originally cataloged under the numerical registration 847 within the local maritime trade registers after being imbued with elementary kinetic enchantments. Rather than functioning as rigid aquatic rudders, the design adapted to the organic movements of the avatar’s body. Over centuries of trade, duplicate specimens crafted under the same workshop pattern spread through the twenty mapped regions of Saṃsāra, frequently passing through the hands of couriers, dockside scouts, and reef-patrol skirmishers. Legends among the coastal guilds tell of an amphibious courier who, while transporting vital dispatches through an active magic storm, leapt cleanly across three oncoming naval boarding cutters by utilizing the sudden updraft of an explosive wave, landing without losing footing or dropping the diplomatic cargo. Because no artisan holds an exclusive copyright on Saṃsāra, varied crafting enclaves across the 73 island countries continue to recreate this exact model, utilizing local materials while adhering to the original schema that grants lower-tier aquatic avatars exceptional balance, maneuverability, and aerial propulsion.
Detailed Tier 1 Stats
* Item Name: Fins 847 of Acrobatics
* Item Tier: Tier 1 (Common)
* Equipment Slot: Fins (specifically fitted to cover or mount directly over biological caudal, pectoral, or dorsal fin structures)
* Armor Check: +1 AC (conforming to the threshold restriction of a maximum of 3 AC per item tier level)
* Item Hit Points: 10 hit points plus the avatar’s maximum hit points (calculated from a base resilience of 10 multiplied by Tier 1, added to the wearer’s current maximum health pool; possesses fixed mundane hit points of 10 when completely unequipped and unattuned)
* Physical Weight: 2 pounds (weighs 0 pounds if placed inside an extradimensional pouch, bag, or storage crypt)
* Suggested Market Value: 45 silver coins (subject to regional scarcity, local taxes, merchant haggling modifiers of 10% times the character’s tier level, and the prevailing conditions of a seller’s market where buyer beware applies)
* Attunement Requirement: Requires simple attunement taking exactly one full minute of deliberate concentration while securely affixed to the avatar’s fin structures; cannot be attuned while kept inside extradimensional storage
* Mind’s Eye Signature: Appears under passive examination as an iridescent, semi-flexible membrane structure radiating a faint ultraviolet sheen consistent with foundational Transmutation and Enchantment weaves
Skills Gained When Openly Worn
* Granted Temporary Skill Points: +2 temporary skill points to the Acrobatics skill pool whenever the item is fastened openly and visible on the avatar’s body.
* Temporary Skill Constraints: These temporary points apply directly to skill check calculations (formula: 10 times character tier level, plus 1d20, plus the 1d4 tier die, plus trained and temporary skill levels), but do not count toward the character’s maximum permanent training cap of 5 plus tier level. If the fins are removed, destroyed, or placed into a concealed container, these temporary points immediately dissipate.
Color
* Membrane Shading: Deep iridescent seafoam green that shifts into bright aquamarine when catching light from Helios.
* Ribbing and Trim: Flexible structural spines dyed a burnished silver-blue, tipped with translucent, milky-pearl edges that glow with faint ultraviolet luminescence under the gaze of true sight.
Multiple Passives Magic
* Hydrodynamic Slipstream: While immersed in liquid or skimming along the surface of water, the magical weave within the membranes smooths the flow of surrounding currents, completely negating the penalty imposed by standard water turbulence on acrobatic flips, body rolls, and rotational dives.
* Kinetic Stability Anchor: Whenever the avatar is subjected to an external force, collision, or turbulent surge that would forcefully displace them or knock them into the prone condition, the fins automatically flare outward, granting advantage on saving throws made to maintain balance and physical orientation.
* Surface Tension Gliding: The trailing edge of each fin constantly repels surface tension, allowing the wearer to transition seamlessly from submerged swimming into an open-air leap without catching or stumbling on wave crests, treating the boundary between water and atmosphere as a stable springboard for tumbling maneuvers.
Multiple Active Magics
* Corkscrew Surge: By spending one action during their turn, the avatar channels internal kinetic momentum through the fin ribbing, executing an instantaneous, tight corkscrew spin that propels them up to 20 feet in any direction through water or up to 10 feet into the air above the surface. This maneuver bypasses obstacles, avoids reactions triggered by movement during that interval, and provides an immediate +2 bonus to the avatar’s AC against attacks made before the start of their next action.
* Vaulting Crest: As an action, the wearer strikes the water surface or a solid surface with the flat plane of the trailing fin to launch their body into an acrobatic vault up to 15 feet vertically or 25 feet horizontally. If used to initiate an attack from above or behind a foe, the avatar adds their 1d4 Tier 1 die to the attack roll, and if successful, the attack deals full base weapon damage with the tier die passing directly into damage.
* Reactive Fin Tuck: When the avatar is targeted by a melee or ranged attack roll while swimming, leaping, or balancing, they can expend a prepared reaction to snap the fins tightly against their flank in an evasive roll. This sudden maneuver immediately adds +2 to their AC against the triggering attack, potentially turning a direct hit into a miss; if the roll misses, the attacker draws a card from the red Failure deck if any of their attack dice landed on a 1.
Tags
Fins, Aquatic, Acrobatics, Common, Tier 1, Worn, Mobility, Transmutation, Enchantment, Kinetic, Water, Lapita, Marine, Agility, Evasion, Baleen, Leap, Balance, Reef, Swimming, Attunement, Reaction
Additional Information
* Repair and Maintenance: If Fins 847 of Acrobatics sustains damage in combat and drops to 5 hit points or fewer, it enters the broken condition, immediately disabling all passive traits, active abilities, and the temporary skill bonuses until fully repaired. Repairing the item requires an artisan with appropriate leatherworking or biological-weaving skills and mundane biological reagents or purified tree sap gathered via a fluid collector, restoring its hit point pool to maximum before it can be re-attuned.
* Destruction Behavior: If targeted directly by a foe during combat and reduced to 0 hit points, the item is destroyed and immediately drops its base component parts, consisting of two sheared flexible baleen struts, three ounces of shredded alchemical membrane, and a drained Tier 1 mundane crystal shard.
* Gestalt and Avatar Limitations: If an avatar possessing Fins 847 of Acrobatics is killed in battle, their physical form disappears in a burst of purple sparks, leaving behind a Tier 1 soul crystal and dropping these fins onto the ground where they fell. If possessed by a higher-tier character who chooses to wear them, the item functions normally without inflicting higher-tier backlash pain, as the pain penalties only trigger when a lower-tier avatar attempts to wear an item belonging to a higher tier than their own character.
* Rest Interactions: Avatars gain nothing from a short rest, meaning that any wear, fatigue, or hit point loss sustained by the avatar while performing exhausting acrobatic feats with these fins can only be recovered through a full daily long rest, consuming proper meals of at least twenty minutes in duration, or utilizing external magical healing items and consumables.
* Upgrade and Rune Pathway: Under the crafting laws of Saṃsāra, this item can be elevated into a Tier 2 uncommon gear piece by taking it to a qualified crafter with a skill rank of 5 or higher. By successfully fusing a complementary mobility rune or kinetic catalyst into the baleen framework at a fee of 15% of the combined item value, the fins gain an additional tier level, increasing their hit points to 20 plus the avatar’s maximum health, raising the AC threshold cap, and converting their Tier 1 damage and skill scaling to Tier 2 values.
Acquisition and Commerce of Fins 847 of Acrobatics
How the Item Might Be Obtained
* Retrieval from Slain Foes or Monsters: In coastal waterways, tidal mangrove swamps, or subterranean sea caverns, avatars may encounter aquatic adversaries such as rogue reef-stalkers, sahuagin raiders, or hostile possessed aquatic scouts that have equipped these fins. When a non-possessed monster wearing the fins is defeated, its corpse remains on the ground or floating in the water, allowing party members to strip the gear directly from the biological fin joints. If the defeated foe was a possessed Tier 1 avatar, its physical vessel vaporizes into a cloud of sparks upon death, dropping its Tier 1 soul crystal alongside Fins 847 of Acrobatics onto the seabed or wharf decking where it can be claimed by spending an action.
* Adventuring Guild and Civic Quest Rewards: Local adventuring guildhalls stationed within major coastal ports—such as those situated across Lapita, Tasian, or Ibero-Maurusian—regularly issue commission contracts to clear predatory beasts from harbor shipping lanes, repair submerged sea-wall foundations, or chart perilous barrier reefs. Because these fins significantly enhance acrobatic survival and mobility in surging ocean currents, local guild masters or appointed military officers frequently offer surplus sets of Tier 1 common aquatic gear as designated quest rewards or bounties for adventurers who successfully fulfill regional maritime tasks.
* Recipe-Driven Crafting and Artisanal Assembly: Avatars possessing the requisite Leatherworking, Biological Weaving, or Alchemical Crafting proficiencies can assemble the item themselves during scheduled downtime away from active exploration. The process requires securing the documented recipe schema for workshop series 847, harvesting aquatic biological membranes, extracting pristine tree saps or organic fluids using a fluid collector to act as binding agents, and utilizing a coin-sized Tier 1 magic crystal as a catalyzing battery to empower the kinetic enchantments within the baleen framework.
* Inheritance Through Avatar Possession: When an unembodied Isekai character soul descends from the sky and seeks out a vessel on Saṃsāra, they may target a native aquatic creature or sentient marine humanoid that already owns and equips these fins. Upon successfully rolling an even number on a d4 to conquer and possess the prospective host, the character instantly claims the physical vessel along with all gear worn at the exact moment of possession, acquiring Fins 847 of Acrobatics as immediate operational equipment without paying monetary fees or crafting expenses.
Types of Shops, Locations, and Commercial Transactions
* Coastal Mom-and-Pop Outfitter Workshops: Saṃsāra has no massive corporate chains or institutional superstores; retail commerce is dominated entirely by independent, family-run artisan shops and specialized crafting stalls. In maritime settlements, these workshops are typically clustered around canal embankments, open-air harbor boardwalks, and tidal wharfs. The storefronts often feature broad outdoor display racks draped in damp kelp to keep organic equipment supple, maintained by master crafters and their apprentices. Avatars inspect the inventory directly, using the passive discernment of their Mind’s Eye to read the structural statistics, resilience, and tier ratings etched into the gear before opening negotiations with the proprietor.
* Buying the Item at a Recognized Merchant: When purchasing Fins 847 of Acrobatics from a legitimate merchant, the transaction operates under standard commercial protocol: * Baseline Cost: The standard baseline suggested value sits around 45 silver coins (equivalent to 4 gold and 5 silver, or 9 electrum), though the true price fluctuates dramatically based on local access, regional proximity to water, and current supply. In landlocked mountain provinces or dry plains countries like Badarian or Archaic, the price can easily surge to 90 silver or higher due to extreme scarcity, whereas coastal island markets may price it lower. * Faction and Guild Discounts: If the buying avatar holds active membership in the merchant’s craft guild or an affiliated trading faction and openly displays their faction badge, they receive a formal discount equal to 10% of the item’s value multiplied by the character’s tier level. For a Tier 1 character purchasing this common item, a 10% reduction applies (10% times Tier 1 = 10%), reducing a 45 silver purchase price down to 40 silver and 5 copper (or 40 silver and 1 nickel). * Banking Integration: In authorized urban storefronts within cities of five thousand or more residents, payment is typically routed through the World Bank run by the god of commerce. The merchant accesses the transaction ledger, and upon completion of the sale, the character’s bank balance—monitored exclusively through their Mind’s Eye—is automatically debited, incurring the standard 1% transaction fee paid by the account holder.
* Selling the Item to an NPC Merchant: When an avatar attempts to sell a surplus or salvaged pair of Fins 847 of Acrobatics to a shopkeeper, the sale is governed by the principles of a strict seller’s market and merchant haggling: * Haggling Variance: The merchant will haggle down the payout based on 10% of the item’s valuation times the character’s tier level. For a Tier 1 seller dealing with a 45 silver baseline, the merchant negotiates the payout down by 10%, offering approximately 40 silver and 5 copper. If the item has suffered wear or combat damage and rests at half its maximum hit points or fewer, the merchant will demand that it be repaired first or deduct substantial repair fees from the payout. * Merchant Refusal Rights: The shopkeeper is under no systemic obligation to purchase the item. If the merchant’s business currently lacks liquid capital, does not specialize in aquatic mobility gear, or has no clientele with biological fin slots, they will refuse the offer entirely, forcing the avatar to seek out another independent shop or travel to a port city. * Official Sales Logging: Legitimate shopkeepers maintain quasi-logs recording what gear was acquired from which individual avatar. Selling unusual or bloodstained gear recovered from naval battles may lead to subsequent questioning by appointed municipal military officers or city guard patrols.
* Black-Market and Shady Dockside Dealing: In the shadowy under-piers and secluded warehouse alleys of major trade hubs, black-market brokers and fence rings deal in illicit, unregistered, or confiscated equipment: * Buying Stolen Stock: Avatars attempting to purchase these fins on the black market must pay the full suggested retail cost with no guild or faction discounts applied, and prices often exceed 50 to 60 silver depending on local demand. * Selling to Fences: When selling to a black-market fence, the broker may pay the standard merchant rate (around 40 silver) or offer up to twice the standard value (up to 80 or 90 silver) if an urgent client needs untraceable aquatic escape gear. The fence keeps their mouth shut, logging no transactions with municipal officials. * Physical Coinage Requirement: Black-market transactions strictly prohibit the use of World Bank electronic ledgers or Mind’s Eye account transfers. All payments must be rendered and received in physical coin—primarily standard minted gold, silver, or approved local non-metal tokens standardized by weight—which avatars must carry in physical pouches or store within weightless extradimensional containers.
* Municipal Taxes and Transit Levies: Moving Fins 847 of Acrobatics across territorial jurisdictions introduces cumulative tax burdens that influence the final retail price: * City Gate and Seaport Access: Individual avatars carrying the gear must pay a personal transit fee of 1 silver per individual when passing through a seaport wharf or entering through fortified city gates. * Border and Transit Taxation: If an itinerant merchant transports a shipment of these fins across a state border, the cargo is taxed at 5% of its assessed value by state border guards. If routed through a country’s neutral Central City, the transit tax is reduced to 1%. Goods brought into an island city or town to be sold at market incur a 3% local sales assessment tax, while goods merely passing through a municipality without changing hands are taxed at 1% by the local warlord or guild authority. If an avatar cannot pay the assessed tax on commercial inventory, the items are impounded by municipal authorities until full payment is rendered.
Tactical Application Across Diverse Environments
Coastal Waters and Coral Reefs
* Defense: * When an avatar is ambushed in shallow tidal waters or caught between coral spurs by jagged polearms or harpoons, the Hydrodynamic Slipstream passive allows rapid lateral banking through the wash of breaking waves. * An incoming trident thrust or crushing claw strike triggers the Reactive Fin Tuck reaction, tucking the flexible baleen close to the body in a tight axis roll that slips the blow along the membrane’s outer curve without catching on surrounding razor coral. * Surging tidal flows pulling over outer reefs threaten to slam swimming avatars into jagged stone outcrops, but the Kinetic Stability Anchor activates to arrest lateral tumbling, preserving balance and keeping the avatar upright.
* Offense: * Navigating around towering reef pillars, the avatar initiates a Corkscrew Surge, accelerating through narrow underwater crevices to instantly clear 20 feet of churning surf and emerge directly behind an encroaching raider. * By utilizing the Surface Tension Gliding feature, the avatar breaches the surface in a fluid arc, engaging the Vaulting Crest action to launch 15 feet into the air above the reef crest before bringing a spear down into an exposed seam of enemy armor. * The granted temporary Acrobatics skill allows an avatar to launch off submerged coral heads, alternating kick-off vectors without losing speed to strike rapidly before foes can stabilize in the surging tide.
Open Deep Ocean
* Defense: * In featureless abyssal depths where massive pelagic predators attack from below or within blinding darkness, the fins continuously stabilize water displacement, preventing the avatar from being tossed into disorienting spins by the wash of passing leviathans. * When an undersea brute lunges with a gaping maw, the avatar spends an immediate reaction to engage the Reactive Fin Tuck, sliding along the downward pressure vortex created by the strike to escape the bite perimeter entirely. * Against wide-area concussive water blasts or depth-charging magic runes, the twin stabilizing fins act as micro-rudders, mitigating rotational disorientation and preventing the avatar from acquiring the dazed or prone conditions in open suspension.
* Offense: * The avatar relies on three-dimensional combat maneuvering, diving into deep thermal layers before activating a Corkscrew Surge to spiral upward through the blind spot of deep-sea predators or submarine hull guards. * Combining the kinetic snap of the baleen ribs with a heavy weapon swing, the avatar uses the momentum of a tight hydrodynamic pivot to deliver a strike that carries full Tier 1 damage alongside the bonus kinetic force of the maneuver. * While pursuing fleeing aquatic foes through deep westward ocean currents, the avatar maintains an aggressive swimming posture, using subtle fin flutters to track erratic evasive swimming patterns without depleting stamina.
Rivers, Inland Canals, and Swamps
* Defense: * In murky river channels, narrow irrigation sluices, or choked mangrove swamps, low visibility and submerged debris create constant entanglement hazards. The Hydrodynamic Slipstream passive repels silt and weeds, keeping the avatar moving freely. * When cornered against muddy banks, pilings, or mangrove roots by shoreline archers, the avatar executes a sudden Reactive Fin Tuck to drop below the waterline, using the muddy wake generated by the fins to obscure their exact position. * When turbulent rapids or opened canal lock-gates threaten to sweep the avatar down violent flumes, the Kinetic Stability Anchor locks the avatar’s trajectory, resisting involuntary sweeps downriver.
* Offense: * In narrow city waterways or port wharfs, the avatar activates Vaulting Crest to spring from the water directly onto canal paths, stone bridges, or moored cargo barges, striking shorebound foes who believed themselves out of aquatic melee reach. * The avatar threads through submerged tree roots or sunken debris by rolling through tight spaces with a Corkscrew Surge, rapidly closing the gap against hostile river skirmishers before they can ready ranged gear. * Striking from river bends, the avatar snaps the trailing edges of the fins against shallow shoals to propel themselves forward in a skittering charge, using the granted Acrobatics training to balance over floating logs or debris to deliver unexpected attacks.
Underground Caverns and Flooded Cave Systems
* Defense: * In subterranean caverns where low stone ceilings hang mere inches above black subterranean pools, ricocheting echoes and sudden rockfalls threaten avatars. The fins maintain precise positional control, preventing the wearer from accidentally striking stalactites. * When an underground monstrosity attacks from a submerged cavern ceiling or crevice, a quick Reactive Fin Tuck allows the avatar to invert their body instantly, presenting the hardened +1 AC baleen spine to glance away incoming blows. * Sudden underground tremors caused by shifting subterranean magma channels can send localized shockwaves through enclosed water reservoirs; the fins immediately counter-oscillate to negate forced knockdown effects.
* Offense: * In cavern sumps with restricted air pockets, the avatar uses a Corkscrew Surge to ricochet off slick stone walls, building kinetic propulsion across enclosed spaces to strike at troglobitic ambuscades. * Where subterranean pools meet dry cavern ledges, the avatar channels a Vaulting Crest to skip effortlessly over slippery, calcite-covered rocks, landing behind subterranean sentries stationed near dark cave thresholds. * Exploiting low-light conditions, the avatar uses the iridescent edge illumination under true sight to coordinate blind maneuvers, executing backflips out of narrow sumps to flank foes across stone shelves.
Atmosphere, Surface Ships, and Floating Megacities
* Defense: * When boarding seafaring carvels, steam-powered gunboats, or traversing the rain-soaked catwalks of sky-floating cloud cities, wet surfaces often compromise footwork. The trailing fins stabilize balance across slippery rigging, wet spars, and slick metal decking. * If an avatar is knocked off a ship deck, wharf pier, or floating tower platform, Surface Tension Gliding and the inherent acrobatic properties allow the wearer to orient themselves mid-fall, angling the descent toward water or safety lines to avoid lethal impacts. * Under fire from deck-mounted ballistas or arcane muskets, the avatar employs a sudden somersault tuck on land, using the kinetic snap of the fins to drop beneath railing cover and avoid targeted missile fire.
* Offense: * During naval boarding operations, an avatar swimming alongside an enemy ship triggers a Vaulting Crest straight out of the ocean, leaping over the high gunwales to land fully balanced upon the quarterdeck in an immediate melee engagement. * On wet boarding planks or rain-swept suspension cables strung between the towers of Copter City, the avatar rolls and tumbles past enemy defensive lines, using enhanced balance checks to slide beneath halberd sweeps and strike at vulnerable support gear. * Leaping between separate steam-wharf cranes or vessel rigging, the avatar uses the trailing aerodynamic drag of the fins to stabilize horizontal jumps, turning high-altitude movement into an offensive dive directly onto hostile command targets.
Perception of Activation:
* Normal Sight: * What is Perceived: A soft, radiant shimmer of seafoam green and bright aquamarine light washing across the surface of the fins, accompanied by a faint pearlescent halo tracing the edges of the silver-blue baleen spines. * Description: As the attunement process locks into the organic tissue, the semi-translucent membranes flare with physical illumination, casting dancing caustic patterns onto the surrounding water, seabed, or floor. * Positives: Visual confirmation of complete activation, allowing the avatar and nearby party members to know immediately that the item’s kinetic enchantments are primed and ready for movement. * Negatives: The bright radiance makes visual stealth impossible in dark caverns or deep ocean environments, broadcasting the avatar’s position to hostile observers within line of sight.
* Physical Touch and Somatosensory Perception: * What is Perceived: A sudden cool, frictionless sensation spreading across the skin and cartilage of the biological fins, followed by a slight tightening sensation as the straps seat firmly. * Description: The fins feel entirely weightless to the wearer, vibrating with a micro-hum that mimics the gentle purr of a idling steam turbine, stripping away the dragging heaviness of normal water resistance. * Positives: Eliminates skin chafing, joint fatigue, and drag, allowing effortless physical posture and swift rotational maneuvering without mechanical strain on the host body. * Negatives: The dramatic reduction in tactile feedback numbs the skin slightly to minor external scrapes, making it harder to feel shallow grazing strikes or subtle brushings from hidden netting.
* Auditory Perception: * What is Perceived: A sharp harmonic chime like glass striking metal, settling into a continuous low-frequency hum that harmonizes with moving currents. * Description: When the arcane battery inside the coin-sized Tier 1 crystal ignites the weave, the resonance rings directly through the wearer’s auditory canals or ear holes, smoothing out ambient rushing noises into a rhythmic thrum. * Positives: Helps the avatar maintain an internal cadence and rhythm for complex tumbling, swimming sequences, and evasive maneuvers. * Negatives: The ongoing low hum can mask very faint, distant ambient sounds, such as the quiet clicking of hidden aquatic predators or whispers from stealthy enemies.
* True Sight (Extra-Sensory): * What is Perceived: A vibrant ultraviolet aura cascading off the tips of the fins in curling vortex lines that map the exact contours of the surrounding weave. * Description: Under the ultraviolet spectrum of true sight, the item ceases to look merely physical, appearing as an interconnected lattice of shifting transmutation runes that actively bend magical currents around the limbs. * Positives: Allows the wearer to visually see planar shears, magical vortexes, and the precise flow vectors of ambient magic in the water, turning invisible currents into readable paths. * Negatives: The ultraviolet glare is intense enough to cause slight visual blooming around the wearer’s lower body, partially obscuring subtle mundane details directly behind the fins.
* Tremorsense (Extra-Sensory): * What is Perceived: A sudden geometric awareness of every vibration, displacement wave, and hydraulic ripple passing through the contiguous liquid or ground medium within thirty feet. * Description: The flexible baleen ribs function as sensitive resonance bars, translating water compressions directly into sensory pulses that pinpoint the precise location, size, and speed of any moving mass in contact with the same water or rock. * Positives: Completely prevents blindside ambushes from submerged foes, revealing invisible or camouflaged stalkers through the pressure wakes of their movement. * Negatives: High-energy disturbances such as depth charges, collapsing cavern walls, or nearby volcanic steam vents cause sensory overload, producing a sharp ringing sensation that distracts mental focus.
* Blind Sight and Hydro-Acoustic Radar (Extra-Sensory): * What is Perceived: A mental, three-dimensional gray-scale topology map constructed from micro-echoes rebounding off solid objects. * Description: As the fins oscillate through liquid, they emit inaudible micro-pulses that bounce back from coral heads, sunken hulls, and cavern ceilings, drawing an instantaneous mental layout of the terrain in the brain. * Positives: Permits flawless navigation, blind tumbling, and high-speed acrobatic evasions in complete, pitch-black water, heavy silt, or ink clouds without relying on ambient light. * Negatives: Echoes reflecting off soft materials like dense kelp beds or organic sludge return fuzzy, indistinct returns, which can lead to misjudging distances to soft, organic hazards.
* Mind’s Eye Resonance (Extra-Sensory): * What is Perceived: An instantaneous overlay of crisp, luminous numerical values and structural parameters floating within the avatar’s internal field of consciousness. * Description: The Mind’s Eye registers the completed attunement by projecting an active stat feed directly into the mind, displaying current item hit points, the +1 AC contribution, the active Acrobatics temporary skill pool, and the single-minute attunement status. * Positives: Grants immediate, unmistakable certainty regarding the operational integrity of the item, alerting the wearer the exact second structural damage brings the fins below half health into the broken condition. * Negatives: The sudden influx of quantified metrics and systemic awareness requires a moment of cognitive focus, creating a split-second pause as the avatar’s consciousness assimilates the item’s operational weave.
Crafting Recipe: Fins 847 of Acrobatics
Materials Needed
* Reagent Base: 6 fluid ounces of specialized ironwood tree sap, extracted in an unrefined state to serve as a vulcanizing bonding agent. * Organic Structural Frame: 2 matched, steam-softened baleen struts harvested from a juvenile whale, large aquatic beast, or reef-skimmer, measuring roughly 18 to 24 inches in length. * Hydrodynamic Membrane: 4 square feet of cured, semi-translucent aquatic creature membrane or rayskin, free of tears or punctures. * Arcane Power Source: 1 coin-sized Tier 1 magic crystal harvested from a slain magical beast or monster, charged with ambient arcane energy. * Binding Medium: 4 fluid ounces of distilled bog mire water or alchemically stabilized biological fluid, collected fresh to preserve ambient mana conductivity. * Sacrificial Component: 1 pair of mundane, serviceable leather fin wraps or swimming webbings, completely consumed during the fusion process to pass along their basic structural form.
Tools Required
* Fluid Collector: A calibrated syringe-and-needle extraction tool utilized to harvest pure biological fluids, tree saps, and mire distillates without introducing contaminants. * Steam Press Chamber: A steam-powered, pressure-sealed curing box operated via rotational mechanical shafts and valves to soften baleen struts and vulcanize the organic resin. * Biological Bone Needle and Thread: Non-reactive carving chisels, bone awls, and treated sinew threads designed for stitching organic hide without grounding out arcane currents. * Alchemical Crucible and Stirring Rod: A heat-tempered glass or ceramic melting pot used to blend the sap, distilled bog fluids, and ground crystal flux over a steady heat source.
Skill Requirements
* Alchemical Crafting: Minimum Skill Level 3 (Required to refine the ironwood sap, balance the fluid reagents, and extract the volatile essence of the Tier 1 magic crystal without causing premature shattering). * Biological Weaving / Leatherworking: Minimum Skill Level 3 (Required to shape, stretch, and fasten the aquatic membrane over the baleen frame without compromising hydrodynamic integrity). * Arcane Mechanics Knowledge: Minimum Skill Level 2 (Required to scribe and seat the kinetic feedback channels connecting the crystal’s power output to the trailing edges of the fins).
Crafting Steps
* Frame Conditioning: * Place the raw baleen struts inside the steam press chamber. * Subject the struts to steady elemental steam pressure for two hours until the dense keratin reaches optimal pliability. * Carefully bend the struts across an arched forming jig to match the biological curvature of an avatar’s fin joints, then allow them to cool and harden in cold seawater.
* Chemical Fusion and Catalyst Preparation: * Pour the 6 ounces of extracted ironwood tree sap and 4 ounces of distilled bog fluid into the alchemical crucible. * Heat the mixture gently, stirring clockwise until the solution changes from an amber color to an iridescent, milky emulsion. * Mount the coin-sized Tier 1 magic crystal in a small containment bracket, then suspend it within the vapor rising from the crucible to saturate its outer crystalline facets with the binding reagents.
* Membrane Cutting and Sacrificial Binding: * Lay the cured rayskin membrane over a clean worktable and cut it into two symmetrical fin covers following the workshop schema 847 pattern. * Place the mundane leather fin wraps directly into the warm alchemical resin. * Stir until the mundane wraps dissolve into the slurry, ensuring the latent physical reinforcement of the leather is transferred directly into the liquid compound.
* Assembly and Structural Stitching: * Align the shaped baleen struts along the structural ribs of the cut membranes. * Using the biological bone needle and treated sinew, stitch the outer edges securely around the frame using an interlocking seam. * Apply the dissolved alchemical slurry liberally along the seams, joints, and inner structural pockets, coating the entire assembly with a waterproof, protective layer.
* Battery Mounting and Arcane Weaving: * Embed the prepared Tier 1 magic crystal into the central mounting junction where the twin fins converge at the mounting cuff. * Using a fine-tipped scribing awl, etch kinetic channels from the crystal mount outward to the trailing edges of both fins, tracing the Transmutation and Enchantment wave pattern. * Feed a steady focus of thought through the crystal until the etched channels illuminate with a faint ultraviolet sheen, confirming that magical energy is flowing evenly through the entire membrane.
* Curing and Inspection: * Submerge the assembled gear into salt water for one full day of downtime to allow the organic resin to vulcanize and harden completely. * Examine the finished piece through the Mind’s Eye to verify that it reads as a Tier 1 Common item possessing 10 base resilience hit points, a +1 AC value, and the full suite of acrobatic traits before clearing it for active attunement.
Fin-Skirt and the Unstraight Swimming of the Scribe-Fish
In the days which were before the count of nine thousand turns of the great wheel, when the Mother of the Moon whose name is Earth-and-Night-Demon had pacified the roaring cauldrons of molten stones, the water of the wide salt-basin did run very swift from the morning-place to the evening-place. Because the gas-ball in the heights of the firmament did pull upon the wetness with two times the weight of older lands, the little swimming people had much trouble of the bones. Their water-arms did flap, but the heavy sea did cast them upon the sharp coral-teeth which bite without having a belly.
At that time there lived an avatar who was called Orom-of-the-Five-Breaths, whose soul had fallen out of the upper cloud-void after dying in a place where iron carts rolled upon flat stones. When Orom did wake inside the cold skin of an eel-bellied swimmer, his thoughts were very tangled with amnesia of the sudden waking. He could not make his tail-parts push straight. Whenever he did seek to swim forward to gather the small shell-creatures for the eating of a meal, the bitter eastern current would twist his middle, and he would roll like an empty gourd, striking his head against the submerged posts of the wharf. The local dwellers of the wharf, who had paid their one silver coin to the harbor-watcher, did laugh with wide mouths, saying that Orom swam like a dead dog that has been salted.
Orom became very angry in his liver. He went unto the house of an artisan of the family-guild, a man named Morv-the-Needle, who did dwell in a small stone shop roofed with wet weeds to keep the leather from cracking. Morv was a maker of things who used no engines of fire nor electric wires, for the great Mother had forbidden such cleverness, but instead possessed three copper syringes of long reach, which were called fluid-pullers.
Morv spoke with a harsh tongue, for he was an old guild-man of fifty winters of labor: “Why do you bring your crooked tail into my stall, you who have no rank and whose gold is not seen? If you wish to swim as the swift fish swim, you must buy of me the skin of an ocean-leaper. But I have no skins that are whole. I have only the shards of an old scheme, which was marked in the stone books with the signs eight, four, and seven.”
Orom did open his mind-window, which is called the Eye of the Mind, and he saw that the shelf held two dried struts of great whale-lip, stiff as seasoned ash-wood, and four pieces of ray-belly which were green like the moss that grows upon a drowned anchor. Between them lay a tiny rock of magic, no bigger than the round coin wherewith a man buys bread, which had been taken from the throat of a marsh-lizard.
“Make for me the eight-hundred forty-seventh garment of the tail,” said Orom, “and I shall dive into the deep black ditch where the water-tax cannot be gathered, and I will bring to you the fat amber-gum from the roots of the drowned trees.”
Morv agreed, for in that country the rule was that a seller may ask what he dares, and the buyer must keep his eyes open lest his skin be peeled. The maker took the bones of whale-baleen and shut them fast inside an iron box through which ran the hot breath of fire-and-water combined, which the people call steam. For two turns of the hour-glass the bones were boiled in the vapor until they were limp like wet grass. Then Morv did bend them across his knee, curving them to match the bent flank of Orom’s fish-body, and he quenched them in salt-soup until they were hard again, but springy like a bow of horn.
Next the maker took his great needle made of an elk-rib and stitched the ray-belly skin around the whale-bones with threads taken from the gut of a swamp-crawler. He took the little magic pebble, which did shine with an invisible violet light that makes the eyes itch if a man looks through the spirit-glass, and he did set it at the junction where the straps cross over the belly. To make the pieces melt into one, Morv took an old pair of leather foot-shoes which Orom had worn before he lost his land-legs, and he threw them into the bubbling pot of tree-sap. The shoes did melt away until no leather was seen, and the virtue of the shoes went into the green skin, so that the tail-garment became as tough as an ox-hide shield.
When the thing was finished, Morv held it out, and the signs upon it read: Fins 847 of Acrobatics. The color of it was like the scum upon a tidal ditch when Helios shines through it at noon-time, both blue and sea-green, with points that did look like pale teeth.
Orom took the item and tied it about his lower parts. He sat upon the stones for one full minute while his soul reached into the item, for until sixty ticks of the world-heart are passed, an item will not know its master. When the attunement was accomplished, Orom felt an icy wind blow down his spine, though he was under the warm sun. His fins did feel as light as dry feathers, and a humming like a thousand angry wasps began in his ears. In his Mind’s Eye, there rose up the sign of one armor-check, and his limbs knew how to leap without his brain commanding them.
Now it chanced that on that very day, the tax-collector of the King’s State, whose name was Baron Krel-of-the-Iron-Pouch, came riding down the wooden wharf upon a water-horse that had scales instead of hair. The Baron was an evil-liver who did not belong to the race of the King, yet had bought his seat through the World Bank by paying many electrum pieces. He looked upon Orom and cried: “You have put upon your tail an item of double fins! The law of the three courts says that whatsoever touches the water of the harbor must pay one part in twenty for the using of the dock, and if the item has a magic pebble within it, the price is three pieces of silver!”
Orom had no silver, for he had given his last copper token to Morv for the pot-resin. Therefore, the Baron commanded his four spearmen, who were broad-shouldered men wearing plates of boiled shark-hide, to cast their hooks into Orom’s flesh and drag him to the stone hole where debtors are kept until they rot.
The first spearman lunged with a three-pronged iron fork. But the eighth-hundred forty-seventh fin-garment was aware of the water-push. Before the iron could pierce the scales, the green membranes snapped shut against Orom’s side like the shell of a clam. This was the Reactive Fin Tuck, which no man can learn from a book. The three-pronged fork glanced off the curved baleen rib with a sound like a cracked pot, doing no harm, and because the attacker struck his weapon upon empty stone, he lost his footing and fell into the mud with his legs in the air.
The other three guards ran forward, brandishing their short swords. Orom did not think, for his amnesia had left his wits dull, but the fins had the memory of their crafting. With one stroke of his tail, he did a Corkscrew Surge, spinning like a drill-bit through the dirty brine. He moved twenty paces in the blinking of an owl’s eye, passing right between the legs of the second guard, causing the man’s water-boots to trip over his own scabbard.
The Baron became black in the face with fury. He drew a great tube of brass which had within it a charge of black dust, made by an alchemist of the city of Tayacian. He aimed the mouth of the tube at Orom’s breast and pulled the trigger. The thunder-stone roared, and a ball of heavy lead flew forth across the foam.
At that instant, Orom struck the water with the flat palm of his second fin. This was the Vaulting Crest. The sea did spit him outward as if he were an olive-stone squeezed between two fat fingers. He rose fifteen cubits into the air, turning three times around his own middle like a dancer upon a rope. The lead ball passed beneath his belly, killing only an innocent mullet that was swimming toward the wharf.
While he was yet hanging between the salt-water and the sky, in the place where birds fly, Orom looked down upon the Baron. The temporary acrobatic virtue of the fins filled his spirit with lightness. He curled his fish-body into a knot and straightened it with a loud slap, coming down out of the air directly upon the neck of the Baron’s scaled horse. The beast took fright at this flying monster and reared backward, pitching the Baron into the deep wharf-mud where the swine-wash is emptied.
The people of the town who had gathered to watch did make a great shout, for they hated the Baron because he took five out of every hundred fish for his own belly. The guild-master himself came forth from his stone porch and said: “This is a great wonder of balance. This avatar has turned upside down three times without casting up his food. Truly, the eight-hundred forty-seventh pattern is an item of fine work, though it is only of the common sort and costeth less than fifty bits of silver.”
Orom did not wait for the military guards to gather with their great nets, for he knew that in a seller’s market the man who has no paper of leasehold is always cast into the cellar. He gave one great twist of his tail-fins, using the Surface Tension Gliding to skip across the foam as a flat stone skips when thrown by a strong boy. He cleared the harbor chain, dodged the great piles of the outer breakwater, and was gone into the wild blue ocean where the currents run toward the setting Helios.
From that day forth, the artisans of the Lapita wharfs made many hundreds of such fins, sewing them always with rayskin and whale-bone, and naming them ever by the number eight-hundred forty-seven, so that any poor swimmer who was born with a crooked spine might leap over the tax-men and laugh from the crest of the waves.
The moral of the tale is that when the currents of life run too heavy for a crooked swimmer, it is better to buy a supple fin than to seek a straight sea; for the man who can balance upon the edge of a foam-crest will ever leap over the spear of the officer, while he who carries only heavy armor will surely sink to the bottom where the crabs do make their market.
Suggested conversions to other systems:
Call of Cthulhu (7th Edition)
Deep-Current Ray Rig
* System and Classification: Call of Cthulhu (7th Edition) Weird Science / Relic of Hyperborean Metallurgy.
* Physical Description: A set of dual pelvic and caudal swimming stabilizers constructed from flexible oceanic baleen ribs and preserved marine ray dermis. The assembly is secured with treated sharkskin harness straps and fitted with a small, cut crystalline focus mounted at the lumbar bracket. When submerged, the apparatus emits a faint violet-blue bioluminescence.
* Equipment Slot and Bulk: Lower Torso / Caudal Appendage or Legs. Counts as 1 standard carry item (encumbrance of 1). Weight is approximately 2 pounds.
* Sanity Loss: 0 / 1 Sanity points upon first witnessing the relic automatically articulate and pulse with independent muscular motion while unattached to an investigator.
* Magic Point Cost: 2 Magic Points per activation of its kinetic propulsion properties.
* Armor Rating: Grants 1 point of physical ballistic/impact armor protection strictly to the wearer’s lower extremities against physical cutting, puncturing, or biting attacks.
* Characteristic and Skill Modifiers: * Swim Skill: +20% percentile bonus to all Swim skill checks. * Dodge and Jump Skills: +10% percentile bonus to Dodge and Jump skill checks while completely submerged in liquid, treading water, or standing upon wave-washed, slick wharf surfaces.
* Specific Mechanics and Maneuvers: * Corkscrew Evasion: When targeted by an underwater attack (such as a lunge from a Deep One or aquatic predator), the wearer may expend 2 Magic Points to perform a rapid axis roll. This grants one Bonus Die on the investigator’s Dodge roll. If the Dodge roll scores an Extreme Success, the attacker automatically loses their balance, granting the investigator one Bonus Die on their next combat maneuver or escape attempt. * Vaulting Breach: By spending 2 Magic Points and executing an action while swimming near the water surface, the wearer can launch themselves 10 feet into the air. This bypasses shoreline obstacles or allows the user to catch onto low-hanging ship gunwales and harbor ropes without making a climb roll, requiring only a regular Jump check to land cleanly on two feet. * Hydraulic Vibration Sense: When fully submerged in stagnant or ocean water, the wearer becomes instinctively aware of any moving physical mass within 10 yards through subtle pressure reverberations, eliminating penalty dice imposed by murky water, total darkness, or ink clouds when locating submerged entities.
* Structural Breakdown and Malfunction: If the wearer suffers a Major Wound from a piercing or cutting attack to the lower body, or if an investigator rolls a Fumble (96-100 or 100 depending on skill level) on a Swim check while using the rig, the crystalline matrix fractures. The rig immediately loses all magical propulsion and temporary skill bonuses, requiring an investigator with Mechanical Repair (at 40% or higher) and Occult (at 30% or higher) to repair over 1d4 days of labor.
Blades in the Dark
The Leaper’s Electroplasmic Skimmer-Fins
* System and Classification: Blades in the Dark Specialized Movement Gear / Sparkcraft Alchemy Apparatus.
* Quality and Tier: Tier I Quality gear item. Available to scoundrels operating in maritime or canal-heavy environments such as the canals of Doskvol.
* Load: 1 Load (Light) when equipped over legs, diving suits, or caudal chassis.
* Primary Purpose: High-speed evasive swimming, canal leaps, and stability on wet roofs, slippery docks, and canal boats.
* System Mechanics and Action Ratings: * Prowl and Finesse Enhancements: The user takes +1d to Prowl or Finesse action rolls when performing acrobatic flips, scaling wet wooden piers, dodging across canal skiffs, or diving into turbulent, freezing water. * Position and Effect Adjustments: In situations where water turbulence, rapid currents, or slippery footing would reduce the scoundrel’s position to Desperate or their effect to Zero, the skimmer-fins stabilize the scoundrel, resetting the baseline position to Risky and granting Standard effect.
* Special Functions and Stress Costs: * Corkscrew Surge: The scoundrel may take 1 Stress to push themselves during an aquatic escape or dockside chase, granting +1 Effect level and allowing an immediate repositioning maneuver that clears canal locks, submerged chains, or barriers without suffering harm from entanglements. * Reactive Tuck Armor: The scoundrel can tick their Armor box on their playbook sheet to absorb or reduce physical trauma targeting their lower body or resulting from a violent impact against water or wharf timbers (reducing Level 2 Harm to Level 1 Harm, or Level 1 Harm to zero).
* Complications and Clock Mechanics: * Electroplasmic Saturation: Operating in canals tainted with leviathan blood or ghost-field echoes can cause the fins to pick up unwanted spiritual resonance. If a Devil’s Bargain is accepted or a complication clock titled “Ghost Resonance” fills (4 segments), nearby spirits are drawn directly to the pale glow of the fins. * Frame Damage: If a resistance roll against structural damage fails or a 1-3 result is rolled on a Desperate dive, the delicate baleen ribbing snaps, disabling the gear until repaired during a Downtime activity with a Tinker roll filling a 4-segment clock.
Dungeons & Dragons (5th Edition / 2024 Revision)
Fins of the Reef Acrobat
* System and Classification: Dungeons & Dragons (5th Edition / 2024 Revision) Wondrous Item.
* Item Rarity and Attunement: Common, requires attunement by a creature that possesses feet, tail fins, or aquatic flippers.
* Armor Class Modifier: Grants a +1 bonus to Armor Class against melee and ranged weapon attacks while the wearer is submerged in water, wet, or balancing on slippery terrain.
* Movement and Speed: * Swimming Speed: While wearing these fins, you gain a swimming speed equal to your base walking speed. If you already possess an innate swimming speed, your swimming speed increases by 10 feet. * Difficult Terrain: You ignore difficult terrain caused by shallow water, rapids, ice, seaweed, or wet wooden surfaces.
* Core Features and Actions: * Acrobatic Stability: You gain advantage on Dexterity (Acrobatics) checks made to tumble, balance, perform acrobatic stunts, or avoid being knocked prone. * Corkscrew Surge: Once on each of your turns, while swimming or submerged, you can take the Dash action as a Bonus Action. When you take this Dash action, your movement does not provoke Opportunity Attacks for the remainder of that turn. * Vaulting Crest: When you breach the surface of water as part of your movement, you can expend 10 feet of movement to launch yourself vertically up to 15 feet into the air or horizontally up to 25 feet across the water surface without requiring a running start or an ability check. If you make a melee attack immediately after completing this vault, you have advantage on the attack roll. * Reactive Tuck: When a creature hits you with an attack roll while you are in water or mid-jump, you can use your Reaction to tuck the fins and roll along the kinetic wave, adding your Proficiency Bonus to your Armor Class against that triggering attack, potentially causing it to miss. You can use this reaction a number of times equal to your Proficiency Bonus, and you regain all expended uses when you finish a Long Rest. Remember that avatars gain nothing from a short rest.
* Item Durability and Structural Statistics: * Resilience and Hit Points: Armor Class 15, 15 Hit Points, immunity to poison and psychic damage. If reduced to 0 hit points, the fins tear apart and drop their component rayskin and cracked focus crystal.
Knave (2nd Edition)
Baleen Ray-Fins of the Tide
* System and Classification: Knave (2nd Edition) Specialized Exploration and Defensive Gear.
* Item Slot and Encumbrance: Occupies 1 Item Slot (worn on lower extremities, feet, or tail).
* Item Quality and Durability: Quality 3 (can withstand 3 breaks or direct sundering blows before being permanently destroyed).
* Armor Defense Bonus: +1 Armor Defense bonus (applies to the character’s total Armor Value, contributing toward the maximum allowable armor cap).
* Mechanical Properties and Stunts: * Aquatic Mobility: The wearer swims at full movement rate (instead of half rate). The user can swim against swift currents, cataracts, and tidal undertows without suffering standard movement penalties. * Dexterity Stunts and Acrobatics: Grants a +2 bonus on all Dexterity checks made to perform physical stunts, tumble through hazardous terrain, balance along narrow spars, leap across water chasms, or resist being thrown off balance. * Wave Vault: Once per combat round, the wearer can expend their regular movement to perform a dramatic vault out of water, leaping over obstacles, harbor chains, or enemy spear ranks up to 20 feet away without requiring an ability roll. If landing on an enemy, the character can make an immediate weapon attack with advantage. * Reactive Deflection: When an enemy scores a direct physical hit against the wearer while in water or on wet ground, the wearer can choose to absorb the blow using the reinforced baleen frame. Doing so reduces the incoming damage by 1d6 points, but forces the fins to tick 1 point of Quality degradation. When all 3 Quality boxes are ticked, the item is ruined and its components can only be salvaged for 10 copper pieces worth of scrap scrap-whalebone.
* Recovery Rules: Repairing a damaged Quality point requires an artisan, 1 hour of downtime, and materials costing 10% of the item’s purchase value per Quality point restored. As avatars gain nothing from a short rest, physical weariness or injuries sustained during underwater maneuvers require a full night of safe sleep and warm food to heal.
Fate (Fate Condensing / Fate Core)
Slipstream Acrobat Fin-Wraps
* System and Classification: Fate Core System / Fate Condensed Extra (Specialized Mobility Gear).
* Aspects: * Function Aspect: Iridescent Baleen Fin-Stabilizers. * Flaw Aspect: Fragile Resonant Crystal Core.
* Stunts: * Hydrodynamic Tumbling: Gain a +2 bonus to Athletics rolls when overcoming obstacles, creating advantages, or defending through evasive acrobatic maneuvers while submerged in water, skimming a liquid surface, or fighting on rain-soaked decks. * Corkscrew Breach: Once per scene, when you succeed with style on an Athletics roll to move through an aquatic or slick zone, you may immediately clear an adjacent zone boundary and place a temporary situation aspect on a target in that zone (such as Off-Balance or Caught in the Wake) with one free invoke, without spending a Fate point. * Reactive Tuck: Spend a Fate point to immediately invoke the aspect Iridescent Baleen Fin-Stabilizers on a physical defense roll against an incoming attack. If this defense succeeds, you may reposition your character one zone away into any body of water or across a slippery surface as a free reaction.
* Durability and Consequences: * Item Stress Track: The fin-wraps possess a dedicated 2-box physical stress track ([1], [2]). * Consequence Slot: Possesses a single Mild Consequence slot (e.g., Cracked Strut, Bent Membrane). When forced to absorb physical harm from targeted sunder attempts or explosive shocks, the user may absorb the damage into the item’s stress or consequence box. If the consequence is taken, the stunt bonuses are halved (+1 instead of +2) until repaired during a quiet scene using Crafts.
Numenera & Cypher System
Hydro-Kinetic Glider Flukes
* System and Classification: Cypher System / Numenera (Discovery & Destiny) Artifact.
* Level: Level 3 (Roll 1d6 to determine level on discovery; base level 3).
* Form: A harness of lightweight, flexible synth-bone slats spanning iridescent biological film, anchored by a dull, glowing amber-blue cypher-crystal at the caudal bracket.
* Depletion: 1 in 1d20 (Roll each time an active function is triggered).
* Effect: * Passive Utility: The wearer is specialized in all swimming tasks and asset-assisted on Speed defense rolls while submerged or moving along the surface of a liquid. * Acrobatic Maneuvers: The item eases all Speed-based jumping, balancing, and tumbling tasks by one step (or two steps if the task takes place in or over open water). * Active Propulsion (Corkscrew Vault): Upon spending 1 point from their Speed Pool, the user activates a burst of kinetic energy, easing their next movement task by two steps and launching up to short range (50 feet) horizontally through water or up to 20 feet into the air from a water surface. If used to initiate an attack against an unaware foe, the attack roll is eased by one step. * Reactive Tuck: When the wearer is targeted by a physical attack while submerged or mid-leap, they can spend 1 Speed point to reflexively curl the apparatus. This eases the Speed defense roll by one step.
* Depletion Manifestation: When a 1 is rolled on the 1d20 depletion check, the amber-blue cypher-crystal fractures into inert salt crystals. The apparatus loses all active functions, Speed easing, and defense benefits, functioning merely as mundane swimming flukes that provide an asset only to mundane swimming tasks until a replacement Level 3 energy cypher is installed via an understanding numenera task.
Pathfinder (Second Edition / Remaster)
Acrobatic Skimmer Fins
* System and Classification: Pathfinder Second Edition (Remaster Core) Item 2 (Alchemical, Apex, Transmutation, Water).
* Usage and Bulk: Worn fins (attached over biological fins, flippers, or lower feet); Bulk L.
* Price: 35 gp (Standard suggested market baseline across port enclaves).
* Item Statistics: Hardness 5, Hit Points 20 (BT 10).
* Passive Benefit: * You gain a +1 item bonus to Acrobatics checks. This bonus increases to +2 when performing Tumble Through, High Jump, Long Jump, or Balance actions in water, aboard moving ships, or across slick terrain. * If you do not possess a swim Speed, you gain a swim Speed of 15 feet. If you already possess an innate swim Speed, you gain a +5-foot status bonus to your swim Speed.
* Activate — Corkscrew Surge: * Action Cost: 1 Action (Manipulate). * Frequency: Once per minute. * Effect: You Swim up to your swim Speed. This movement does not trigger reactions (such as Reactive Strike) triggered by movement. If you end this movement adjacent to an enemy, you can make an immediate Strike with a light weapon or natural attack with a +1 circumstance bonus to the attack roll.
* Activate — Vaulting Crest: * Action Cost: 2 Actions. * Frequency: Once per 10 minutes. * Effect: You propel yourself from a body of water into the air, performing a High Jump or Long Jump without requiring a Stride first. You calculate the jump distance as though you rolled a critical success on an Athletics check, leaping up to 15 feet vertically or 25 feet horizontally. You land on your feet on solid ground or re-enter the water without taking falling damage.
* Activate — Reactive Tuck: * Action Cost: Reaction. * Trigger: An enemy misses you with a melee attack while you are in water or balancing. * Effect: You immediately Step 5 feet through the water, leaving the attacker flat-footed (off-guard) against your next attack before the end of your next turn.
Savage Worlds (Adventure Edition – SWADE)
Reef-Dancer Fin Harness
* System and Classification: Savage Worlds Adventure Edition (SWADE) Minor / Major Arcane Device (Weird Science / Alchemy).
* Item Attributes: Weight: 2 lbs. Cost: $450.
* Minimum Strength: d4.
* Power Points: 10 Power Points (recharges at the rate of 1 point per hour).
* Innate Properties: * The wearer gains a +2 bonus to Athletics rolls made for swimming, leaping, and balancing maneuvers. * Pace: Grants Pace 6 in water, or adds +2 to existing Swimming Pace. Water turbulence and slick footing do not count as Difficult Ground. * Parry Modifier: Grants a +1 Parry bonus against melee attacks while floating, submerged, or wet, provided the wearer is not Shaken or Bound.
* Embedded Powers: * Speed (Corkscrew Surge): * Power Points: 2. * Range: Smarts (Self). * Duration: 5 rounds. * Effect: Doubles the character’s movement Pace in water and grants the Quick trait for the duration. With a Raise on the activation roll, running incurs no multi-action penalty. * Deflection (Reactive Fin Tuck): * Power Points: 2. * Range: Self. * Duration: 5 rounds. * Effect: Incoming attacks targeting the user suffer a -2 penalty (-4 with a Raise on activation) as the articulated fins twist and slip incoming blades and missiles through dynamic hydro-kinetic deflection.
* Malfunction Rule: If the user rolls a Critical Failure on any Athletics or Arcane Skill check while utilizing the device, the harness short-circuits. The user becomes Distracted, and the harness loses all stored Power Points, requiring an hour of repair work with a successful Science, Repair, or Weird Science check to restore functionality.
Shadowrun (Sixth World)
Aquatic Vector-Fins Model 847
* System and Classification: Shadowrun Sixth World (SR6) Specialized Amphibious Gear / Armor Modification.
* Gear Placement: Mounted over lower extremities, aquatic cyber-limbs, or biological caudal appendages; occupies 1 Armor Modification Slot.
* Essence Cost: 0 (External Gear / Harness). If permanently implanted as bioware or wetware-augmented bio-fibers, Essence cost is 0.2.
* Availability and Cost: Availability 2 (Legal), suggested baseline cost 1,800 Nuyen (subject to regional aquatic gear shortages, fixer availability, and black-market markups).
* Defense Rating and Armor Contribution: * Adds +1 to the wearer’s Defense Rating when targeted by physical or melee attacks while immersed in liquid, swimming, or balancing across slick docks, rain-soaked catwalks, and ship hulls. * Contributes +1 Armor against physical damage targeting the lower body or resulting from collisions with submerged structures.
* Skill Modifiers and Edge Mechanics: * Athletics Skill: Grants a +2 dice pool modifier to all Athletics Tests made for swimming, leaping, acrobatic tumbling, or maintaining balance on slippery surfaces. * Edge Generation: While operating in water or immediately breaching the surface, the wearer gains 1 point of Edge whenever their movement or evasive maneuvering causes their Defense Rating to exceed the attacker’s Attack Rating by 4 or more, ignoring standard non-Edge limitations for aquatic environmental penalties.
* Action Economy and Tactical Maneuvers: * Corkscrew Surge (Minor Action): While swimming, the user expends a Minor Action to trigger an automated kinetic compression in the synthetic baleen ribs. The character instantly moves up to their Sprint rate through water without taking fatigue penalties, completely ignoring physical movement-based intercept attacks during the maneuver. * Vaulting Crest (Major Action): The user snaps the fins against the water’s surface to launch up to 5 meters vertically into the air or 8 meters horizontally onto a dry platform, ship deck, or barge. If the character executes a Close Combat Attack immediately upon landing, they gain a +2 Attack Rating bonus for that strike. * Reactive Tuck (Anytime Reaction): When targeted by an attack while submerged or mid-vault, the user spends an immediate Reaction to tuck the fins tight against the body. This grants an immediate +2 bonus to the Defense Test pool against that single attack. If the attacker fails to score any net hits, their attack is completely deflected along the water slipstream.
* Glitch Mechanics and Structural Integrity: * If an Athletics or Defense Test results in a Glitch while using the fins, the internal kinetic crystal stabilizer stalls, disabling all passive bonuses and Edge generation until rebooted using a Minor Action. * On a Critical Glitch, one of the primary lateral struts fractures, inflicting the broken condition on the unit and reducing the wearer’s swimming movement by half until repaired with an Engineering + Logic (2) Extended Test during downtime. Remember that avatars gain nothing from a short rest.
Starfinder (Second Edition)
Pelagic Aerofins of the Manta
* System and Classification: Starfinder Second Edition Item 2 (Alchemical, Tech, Water).
* Equipment Slot and Bulk: Worn fins (attached over biological fins, flippers, or environmental suit boots); Bulk L.
* Suggested Market Value: 35 Credits (subject to station access, free-trader merchant availability, and local planetary trade tariffs).
* Durability and Structural Statistics: Hardness 5, Hit Points 20 (Broken Threshold 10). If reduced to 0 hit points, the item is destroyed and leaves behind inert poly-ceramic struts and a drained battery crystal shard.
* Passive Attributes: * Provides a +1 item bonus to Acrobatics checks. This bonus increases to +2 when performing Tumble Through, High Jump, Long Jump, or Balance actions in zero-gravity environments, liquid environments, or across hazardous, oil-slicked spaceship hull surfaces. * Swimming and Zero-G Speed: Grants an innate swim Speed of 20 feet (or a +10-foot status bonus to an existing swim Speed). The user treats aquatic micro-currents and liquid drag as normal terrain rather than difficult terrain. In zero-gravity, the directional flukes function as vernier fins, granting a +5-foot bonus to maneuverability strides along station bulkheads.
* Active Abilities: * Corkscrew Burst (1 Action – Manipulate): Once per minute, the user activates the internal kinetic battery cell to execute a rapid spiral through liquid or zero-g space, moving up to their full swim Speed. This movement does not trigger reactive strikes or opportunity fire. If this movement ends within melee reach of a hostile target, the user may make an immediate Strike with an agile or finesse weapon, adding a +1 circumstance bonus to the attack roll. * Vaulting Breach (2 Actions): While swimming just beneath the surface of a liquid, the user expends two actions to breach upward, vaulting up to 20 feet vertically or 30 feet horizontally onto dry decking, low catwalks, or vessel superstructures. The character lands firmly on their feet without needing an Acrobatics check and ignores landing damage from that height. * Reactive Hydro-Tuck (Reaction): * Trigger: An enemy misses the user with a ranged or melee attack while the user is submerged, airborne, or operating in zero-g. * Effect: The user rapidly curls the outer flukes, snapping through the wake to Step 5 feet in any direction, throwing off the attacker’s targeting arrays and leaving the enemy off-guard against the user’s next strike before the end of their next turn.
Traveller (Mongoose 2nd Edition / 2022 Update)
Sub-Surface Kinetic Hydro-Fins
* System and Classification: Mongoose Traveller (2nd Edition / 2022 Update) Specialized Aquatic Survival & Boarding Equipment (Personal Gear).
* Tech Level: TL 10 (Advanced Composite Hydro-Dynamics).
* Mass and Encumbrance: Mass 1 kg (Negligible encumbrance when worn around diving gear, vacc-suit boots, or natural aquatic tail flukes).
* Standard Cost: Cr 450 (Subject to starport class, local planetary trade law codes, and law level enforcement).
* Skill Modifiers and Task Checks: * Athletics (Dexterity): Grants a DM+2 bonus on all Athletics (Dexterity) checks involving balancing on moving sea vessels, climbing slick mooring lines, or executing acrobatic leaps across water-slicked surfaces. * Athletics (Endurance): Grants a DM+1 bonus to Athletics (Endurance) checks made to resist physical fatigue or exhaustion when swimming against heavy tides, oceanic conveyor currents, or severe wave wash.
* Operational Mechanics: * Aquatic Movement: Multiplies swimming movement speed by two, granting a standard swimming speed of 12 meters per combat round (or 18 meters per round during a double move). * Breaching Maneuver: By using a Minor Action prior to jumping out of water, the traveler can clear sea barriers, low gunwales, or pontoon docks up to 4 meters above the water line without rolling. An Athletics (Dexterity) check is required only if attempting to breach while carrying heavy cargo (encumbrance exceeding standard limits). * Evasive Slipstream: When targeted by ranged fire or harpoon launchers while swimming or treading water, the traveler may declare an Evasive Reaction. This imposes a DM-2 penalty on the attacker’s roll (or DM-3 if the user dedicates their full combat turn to evasive maneuvers). * Sonar/Hydro-Acoustic Awareness: Incorporates passive vibrational sensors along the trailing edge of the composite fins, allowing the traveler to detect the heading and engine displacement of any watercraft, torpedo, or large sea creature within 100 meters, eliminating environmental darkness or water turbidity penalties for locating submerged contacts.
* Maintenance and Battery Power: * Operates on a standard TL 10 micro-power cell capable of sustaining 24 continuous hours of active kinetic assistance. * If subjected to deep underwater explosions (such as depth charges or concussion grenades), the traveler must make an Average (8+) Athletics (Dexterity) check. On a failure, the fin control linkages jam, negating all DM bonuses until serviced with a Mechanic check taking 10 minutes of bench work.
Warhammer Fantasy Roleplay (4th Edition)
Tide-Dancer’s Baleen Flukes
* System and Classification: Warhammer Fantasy Roleplay 4th Edition (WFRP 4e) Specialized Trappings / Magical Wonder.
* Trapping Category: Worn Clothing / Aquatic Armor (Fitted over lower limbs, aquatic tails, or feet).
* Encumbrance: Encumbrance 0 (Encumbrance 1 if packed away dry in a leather travel knapsack).
* Price and Availability: Exotic Availability (Found primarily in coastal Marienburg outfitter shops, Sea Elf enclaves, or through specialized smuggling rings along the River Reik); suggested price 4 Gold Crowns and 10 Silver Shillings (subject to merchant haggling, local trade tariffs, and coastal scarcity).
* Armor Points: 1 Armor Point (AP 1) protecting the Legs / Tail location against slashing, piercing, and bludgeoning attacks. This armor point stacks with physical leathers but bypasses standard encumbrance penalties due to its flexible, water-repelling construction.
* Skill Bonuses and Mechanical Qualities: * Qualities: Fine, Flexible, Lightweight. * Athletics and Dodge: Grants a passive +10 bonus to all Athletics Tests and Dodge Tests made while swimming, balancing on wet ship decks, or treading marshland. * Swim Tests: The wearer automatically passes any Easy (+40) or Average (+20) Swim Test without needing to roll, and adds +20 to challenging Swim Tests made against rough ocean swells, rapids, or tidal vortexes.
* Combat Traits and Maneuvers: * Advantage Generation: Whenever the character succeeds on an opposed Dodge Test or Athletics Test while in water or on slippery terrain, they immediately gain +2 Advantage (instead of the usual +1) as the kinetic spring of the baleen propels them into an advantageous tactical position. * Corkscrew Vault: The character may spend 1 Advantage to launch themselves from water onto a riverbank, wharf, or ship’s deck up to 4 yards higher than the water surface, landing on their feet and ready to attack without expending their Move action. * Reactive Deflection: When struck by a melee attack while in water, the wearer may spend 1 Advantage as a Free Reaction to snap the trailing fin into the weapon’s path. This reduces the incoming attack’s Success Levels (SL) by 2. If this reduces the attacker’s SL below 0, the attack misses completely and the attacker gains the Prone condition if standing on wet boards or mud.
* Wear and Fumble Hazards: * If the character rolls a Fumble (a roll of 96–100 or matching double digits resulting in failure) during an Athletics, Dodge, or Swim Test while wearing the flukes, the delicate alchemical membrane tears. The item gains 1 point of Damage, losing its active features and skill bonuses until repaired by an artisan or leatherworker with a successful Trade (Leatherworker) or Trade (Apothecary) Test during downtime. * Any avatar wearing this gear recovers wounds and fatigue strictly through extended long rests, hot sustenance, or professional chirurgery, as avatars gain nothing from a short rest.