Leviathan, Prince of Stygia

The Two Faces of Leviathan

Leviathan has worn innumerable identities, but two bodies recur so consistently that infernal records treat them as his principal forms. Neither is merely an illusion. Through the ability known as Eternal Traitor, the shape Leviathan assumes becomes his actual current body and is extraordinarily difficult to expose as a transformation.

Prince Form

The Eternal Traitor

In his favoured smaller body Leviathan stands approximately twelve feet tall. He resembles a powerful malefircarim with black-grey scaled flesh, broad webbed claws, an aquatic fluke-like tail and enormous black eyes that never appear to blink.

This is the body of the conspirator, diplomat, tempter and infernal prince. It allows Leviathan to walk through courts, fortresses, ships and mortal structures that could never accommodate his gigantic aquatic body.

Combat profile: Large. Full psionics, spellcasting, supernatural memory powers and Lord abilities remain available. Prince Form does not gain the colossal body’s Swallow Whole, Improved Grab, Sealed Scales or Vapor of Oblivion.

Leviathan Form

The Lord of Oblivion

Leviathan’s most infamous body is approximately one hundred and eighty feet long. A smooth bullet-shaped head bears glittering black eyes and nine ranks of razor teeth. Smoke continually pours from recessed nostrils.

An immense humanoid upper torso rises from a whale-like lower body. Titanic webbed claws project from his sides, while the body terminates in a colossal spiked tail. Black and grey scales lock together like plates of infernal adamant.

Combat profile: Gargantuan in modern rules and Colossal in 3.5e. This body gains the enlarged bite, Improved Grab, Swallow Whole, immense reach, Sealed Scales, Vapor of Oblivion and Leviathan’s exceptional defence against mind-affecting powers.

Leviathan at the Table

The D&D 3.5e creature remains the mechanical master. Pathfinder 1e and D&D 5.5e / 2024 translate the same Leviathan rather than replacing him with unrelated versions. The two principal bodies, 75th-level telepathy, memory destruction, imprisonment, Diadem of Amnesia and territorial Lordship are retained across all three systems.

Leviathan Imprisoned in the Ice

Imprisonment is not a third form. It is a supernatural encounter state imposed upon Leviathan by Asmodeus.

The prison normally fixes Leviathan in his colossal body at Tantlin. Exceptional summons and direct infernal permission can temporarily permit him to assume Prince Form or manifest partly outside the ice.

D&D 5.5e / 2024 — Imprisoned State

• Leviathan’s Speed becomes 0.
• He cannot make Bite, Claw, Tail or Swallow Whole attacks through the prison.
• He cannot voluntarily teleport or plane travel with the imprisoned body.
• Ordinary physical or magical attacks cannot establish Leviathan’s body as a valid target through the intact prison.
• Telepathy, Spellcasting, Psionic Mastery, Confer Ignorance, Subvert the Senses, Strip the Memory, Call Devils, Diabolical Decree and Might of Hell remain available wherever their targeting requirements can legitimately be satisfied.
• A willing barregon may serve as a remote origin point through Forget the Flesh.
• If a summoning genuinely manifests Leviathan outside the prison, he may use the form permitted by that summoning. When the effect ends he returns to imprisonment unless the prison itself has actually been overturned.

D&D 3.5e — Imprisoned Adjustments

While fully imprisoned Leviathan has Dexterity 0, Speed 0 and no physical attacks.

His Reflex save becomes +36. He uses his Intelligence modifier in place of Dexterity for Initiative and for ranged spell or psionic touch attacks where the prison permits such effects.

His Initiative becomes +17 and his corrected ranged touch attack becomes +72.

The prison cannot be transported by Leviathan’s own teleportation, plane shift or psychoportive abilities. Powerful external summoning and calling effects may nevertheless manifest him elsewhere under their specific terms.

Pathfinder 1e — Imprisoned Adjustments

Dexterity becomes 0 and Speed becomes 0 while the prison fully restrains Leviathan. Physical natural attacks, grapples and Swallow Whole are unavailable.

Psionic, supernatural and spell-like abilities specifically capable of functioning through the prison remain available, and barregon vessels remain valid origins for Forget the Flesh.

Forget the Flesh

Leviathan’s greatest answer to imprisonment is not escape. It is making the prison strategically irrelevant.

Willing barregons can become remote sensory and psychic stations. Through them Leviathan observes conversations, employs telepathy, projects enchantments and directs supernatural abilities whose rules allow a remote origin.

The barregon does not become another Leviathan. It retains its own body, hit points and defences. Destroying the vessel breaks the connection rather than inflicting the vessel’s wounds upon Leviathan’s true body.

The Great Iceberg — Lair Actions

On Initiative count 20 while an encounter occurs within Leviathan’s iceberg, its immediate waters or the memory-saturated passages surrounding the prison, Leviathan chooses one of the following effects. The same effect cannot be used on two consecutive rounds.

• Styx Surge. Black water floods a 60-foot-radius region. Creatures there make a DC 34 Intelligence saving throw or take 44 (8d10) Psychic damage and become Memory-Scoured until the next Initiative count 20.
• Black Ice. Ice erupts around up to three creatures. Each must succeed on a DC 34 Strength saving throw or become Restrained. A restrained creature may use an Action to repeat the save.
• Forgotten Crime. Up to six creatures hear recollections they had tried to bury. Each makes a DC 34 Wisdom saving throw or becomes Frightened until the next Initiative count 20.
• False Passage. Leviathan rewrites perception of a corridor, stairway, doorway or open stretch of ice. Until the next Initiative count 20, creatures other than Leviathan and his servants treat one 60-foot cube as Heavily Obscured.
• Barregon Conduit. One willing barregon within the lair immediately becomes a vessel for Forget the Flesh without requiring Leviathan’s normal action expenditure.
• Frozen Jurisdiction. Unauthorised teleportation and planar travel fail within a selected 120-foot-radius region until the next Initiative count 20.

The Shadow of Leviathan

Leviathan’s imprisonment confines his colossal body, not the pressure of his presence. The Great Iceberg, the harbour of Tantlin and the surrounding reaches of Stygia have absorbed his telepathy, his hunger for memory and his long association with the Styx. These effects are strongest close to the prison and weaken with distance.

• Waters of Forgetting — 13 miles. Natural water, meltwater and ice become psychically sympathetic to the Styx. A non-fiend that drinks untreated water from the region and then finishes a Long Rest must succeed on the regional saving throw or awaken with one minor personal recollection missing, displaced or replaced by an equally minor false detail. This effect cannot remove a proficiency, spell, class feature, identity, major bond or other mechanically significant knowledge. The altered recollection normally returns after the creature’s next Long Rest outside the region.
• The Unremembered Road — 13 miles. Routes resist recollection. A traveller can remember that a place exists and may remember important landmarks, but cannot reliably retrace a complicated route from memory alone once more than 1 hour has passed. Maps, written directions, physical trail markers, tracks and other external records function normally unless separately altered.
• Whispers Beneath the Ice — 6 miles. When an intelligent creature sleeps, Leviathan may establish a one-way telepathic whisper into its dreams. He may speak, ask questions, offer a bargain or present an image or remembered scene. This regional effect does not itself Charm, compel or read the creature’s thoughts, and the dreamer may refuse to answer.
• Black Ice Remembers — 6 miles. Large formations of old ice sometimes retain emotional residue from creatures that passed nearby. A creature that maintains bare physical contact with such ice for 1 minute may experience a brief image, phrase, sensation or emotional impression from a strongly felt event that took place nearby. Leviathan can deliberately seed these impressions with false fragments. A false fragment is not itself a rewritten memory and can be questioned or contradicted by other evidence.
• Eyes of the Eternal Traitor — 6 miles. Snakes, eels, lampreys and similar creatures increasingly develop glossy black eyes and unnaturally quiet behaviour. Leviathan may perceive through one such creature for up to 1 minute at a time, using its ordinary senses. He can maintain only one such viewpoint at once. This does not create line of effect for attacks or powers; a barregon vessel and Forget the Flesh remain necessary for that stronger form of remote manifestation.
• Stygian Silence — 3 miles. Magic, psionics and supernatural divination attempting to investigate memories that Leviathan personally erased, suppressed or altered detect the absence or disturbance but do not automatically reconstruct what was lost. Recovery still follows the restoration rules of Strip the Memory, Subvert the Senses, Confer Ignorance or the Diadem of Amnesia, as appropriate.
• The Frozen Lie — 1 mile. When a written record, carved inscription or displayed image directly contradicts a falsehood Leviathan is actively protecting, frost may spread over the relevant words or details. The record is not destroyed: warming, scraping or otherwise clearing the ice reveals the original evidence. The effect therefore conceals inconvenient records rather than rewriting them.
• The Prince Is Listening — 1 mile. Whenever a creature knowingly speaks Leviathan’s name aloud, Leviathan becomes aware of that creature’s exact location at that moment, unless a cosmic or artifact-level effect specifically blocks his awareness. He may immediately open telepathic communication if range and other restrictions permit. This does not provide continuous tracking after the moment passes.

Persistence of the Region

A temporary summoning, projection or manifestation of Leviathan does not suspend these regional effects. His presence has saturated Tantlin across ages of imprisonment and continues to emanate from the prison while his connection to Stygia remains intact.

If Leviathan is permanently destroyed or permanently removed from Stygia, the effects caused specifically by him begin to fade after 1d10 days and disappear after 30 days. Effects arising independently from the River Styx, Stygia itself or another infernal power remain.

The Diadem of Amnesia

Strip the Memory

Leviathan is frequently summoned not for wealth, victory or forbidden knowledge, but because someone wants evidence to disappear from living minds.

He can erase witnesses, rewrite recollections, remove a client’s own memory of a deed and suppress the psychological or magical consequences that rely upon remembering it.

Infernal Claims

Strip the Memory does not automatically determine the final destination of every creature who benefits from it.

An infernal claim exists where the bargain itself contains a pledge of the soul, infernal allegiance, binding obligation, supernatural lien or another recognised means by which Hell can assert possession.

Leviathan prefers to conceal such terms inside agreements apparently concerned only with secrecy, memory or absolution.

The False Atonement

Leviathan can make a client appear to have escaped the consequences of an act by removing the memory upon which those consequences operate.

This can resemble Atonement from the outside, but it does not constitute genuine restitution, forgiveness or cancellation of an independent contract, oath, debt, curse or claim.

The Government of Ignorance

Leviathan does not believe knowledge is inherently wicked. Knowledge is useful when it belongs to him. His doctrine is aimed at everyone else.

He encourages rulers to divide responsibility until no subordinate feels responsible for the complete act. Orders become narrower. Reports become selective. Archives lose inconvenient pages. Officials learn to ask only the questions necessary to preserve their own position.

This is Leviathan’s ideal order: a hierarchy in which every participant knows enough to obey but too little to understand the entire machine.

He rarely needs a servant to believe an obvious lie. It is usually sufficient to provide a smaller truth and ensure that the rest of the evidence never reaches them.

Lord of the Fifth

Leviathan rules Stygia as one of the territorial Lords of the Nine. His power inside the Fifth is enormous, but Stygia is not an independent sovereign state.

Hell is one infernal dominion divided into nine great jurisdictions.

Leviathan therefore rules beneath Asmodeus , Lord of Nessus and Overlord of Hell.

The Styx

The River Styx is both road and weapon in Stygia. Its waters threaten memory and identity, while ports, patrols and ferries turn the river into one of the major transportation networks of the Fifth.

Leviathan’s connection to the river is exceptionally close. Memories carried through its black waters are a source of fascination, hunger and power to the Lord of Oblivion.

The Barregons

Among Leviathan’s most valuable servants are the barregons , gate devils closely associated with Stygia, infernal waterways and the River Styx.

Their unusual resistance to memory destruction makes them particularly useful to a ruler whose own powers consume recollection and identity.

The Eternal Traitor

Eon XVI — Organised Devil Civilisation

Hell itself is vastly older than the civilisation that later comes to dominate it. Durable infernal institutions emerge much later, as ranks, legions, courts, fortresses and territorial offices begin to survive individual rulers.

Leviathan belongs to the ancient generation of major powers remembered from the early political history of organised Hell.

The Luciferian Settlement

Under Lucifer’s securely remembered infernal regime, Leviathan holds Stygia as Lord of the Fifth beneath the sovereign throne.

Even in the oldest surviving political traditions he is remembered as a conspirator whose alliances rarely survive his ambitions.

The Asmodean Ascendancy

When Asmodeus overthrows the Luciferian regime, Leviathan survives the succession and remains a major infernal power.

His ambition does not disappear with the change of sovereign. Later infernal traditions preserve numerous stories of plots aimed at discovering, stealing or circumventing Asmodeus’s power.

Conflicting Records of Bensozia

Older Stygian accounts claim that Leviathan abducted Bensozia while seeking the secret of Asmodeus’s power, that Geryon betrayed the plot and that Leviathan killed Bensozia before Asmodeus appeared.

The present master chronology does not require every detail of that account to be literal history. What is securely retained is the political outcome: Leviathan loses Stygia, Asmodeus imprisons him and Geryon takes the Fifth.

The Great Fall and Geryon’s Stygia

During the broad political age surrounding the Great Fall, Leviathan is removed from territorial government and sealed within the frozen reaches of Stygia.

Geryon becomes Lord of the Fifth in his place. Leviathan’s physical body is confined, but his telepathy and remote vessels ensure that imprisonment never becomes true political silence.

Dies Irae

The Days of Wrath destroy the previous balance among the Lords. At the decisive confrontation Geryon signals his loyalty to Asmodeus, yet the post-war settlement still removes him from Stygia.

Leviathan returns as Lord of the Fifth.

The restoration is deliberately incomplete. The office returns while the great prison remains. Leviathan therefore governs an entire Perdition while his physical body remains trapped beside its principal port.

The Gathering Darkness

In the present infernal age Leviathan continues to seek greater influence over Hell while remaining beneath the sovereignty of Asmodeus.

His most dangerous campaigns are indirect: erase a record, create a false recollection, compromise an official, acquire a forgotten secret, control a witness and eventually make every survivor believe that the new arrangement has always existed.

Enemies, Rivals and Useful Allies

Using Leviathan

While Imprisoned

An imprisoned Leviathan encounter should not be run as an ordinary fight against an immobile collection of hit points. His body is inaccessible while the prison remains intact.

Instead he acts through barregon vessels, Call Devils, psionics, altered senses, memory destruction and the environment of Tantlin itself.

Prince Form

Prince Form is Leviathan at his most tactical. He can move through conventional fortresses, ships and chambers while retaining his full telepathy and supernatural powers.

Against dangerous opponents he normally attacks perception before flesh. Subvert the Senses, Mindwipe and Psychic Crush create weaknesses before he commits to direct melee.

Leviathan Form

The colossal body turns a battle into an environmental event. Leviathan prefers deep water, the Styx or another open region where his mass, reach and swimming speed become decisive.

He uses his Bite to seize dangerous enemies, Swallow Whole to isolate targets whose psychic defences have already been damaged and Hell’s Fire to destroy distant formations.

Changing Form

Leviathan changes body because the situation demands it, not because transformation offers another pool of hit points.

If a cramped confrontation opens onto the Styx, he may become the great Leviathan. If opponents retreat into a fortress, he may become the Prince and follow. All wounds and expended resources accompany him.

Summoning Leviathan

Rituals addressed to Leviathan traditionally involve cold water, carved blocks of ice, silver-filled sigils and deliberate acts of memory destruction.

The ritual space must remain cold enough that no carved line softens or melts.

The oldest surviving rites require fifteen humanoids whose memories have already been deliberately erased. Their emptied recollections become sympathetic channels through which the Prince of Stygia can establish contact.

As the invocation nears completion the water darkens and begins to rotate. Cold pressure fills the chamber. A vast shadow moves below the surface before impossible black ice rises through it.

Ordinary Successful Invocation

Most rites do not release Leviathan. He appears as a shadow within the ice, communicates telepathically or projects himself through the water.

Prince Manifestation

Exceptionally powerful summonings can manifest Leviathan’s roughly twelve-foot Prince Form partially or completely outside the prison for the duration of the effect.

Leviathan Manifestation

Rarer still are epic rites capable of manifesting the full colossal Leviathan Form.

Neither manifestation permanently breaks the prison. When the summoning ends, Leviathan returns to Tantlin unless the campaign has genuinely overturned Asmodeus’s imprisonment.

Leviathan in Mortal Art

The name Leviathan carries a much wider body of mythic and literary imagery than the particular infernal being described here. SpiralWorlds retains that inherited maritime imagery while giving the Lord of the Fifth his own cosmological, political and mechanical identity.

Leviathan in Myth and Legend

These external videos are retained as comparative mythological and historical context. They discuss older mortal traditions surrounding the name Leviathan and do not define the identity, history or rules of the SpiralWorlds Lord of Stygia.

What is the Leviathan? and What can it tell us about Ancient Religions? Trey the Explainer — comparative ancient religion, sea-serpent traditions and the wider mythological background of Leviathan. What is the Leviathan? — Exploring the Gargantuan Monster of the Sea Mythology & Fiction Explained — a concise survey of Leviathan, sea-monster traditions and later infernal associations.

Continue Through Hell

Publication Notes

The D&D 3.5e mechanical foundation of this creature descends from The Gates of Hell / Grimoire of Cosmic Entities Volume One, credited on the legacy SpiralWorlds entry to Eli Atkinson, William Church and Serge W. Desir Jr., with the original Leviathan concept credited there to Serge W. Desir Jr.

This SpiralWorlds reconstruction corrects the legacy hit-point total, restores the missing Telepath power-point reserve, separates Prince Form from Leviathan Form, distinguishes both forms from the imprisonment state, adds lair and regional effects around Tantlin, reconciles infernal rank with the current Hell hierarchy and translates the same underlying monster into Pathfinder 1e and D&D 5.5e / 2024.

Where older infernal material conflicts with the current SpiralWorlds master chronology, the present Hell, Stygia, History of Hell and Stratification records control canon.