Liopleurodon

Huge beast, unaligned

---

Armor Class: 17 (natural armor)
Hit Points: 195 (17d12 + 85)
Speed: 5 ft., swim 50 ft.

---

STR	DEX	CON	INT	WIS	CHA
23 (+6)	16 (+3)	21 (+5)	3 (−4)	14 (+2)	7 (−2)

---

Saving Throws: Dex +7, Con +9, Wis +6
Skills: Perception +6, Stealth +7
Damage Resistances: bludgeoning, piercing from nonmagical attacks
Damage Immunities: cold
Condition Immunities: frightened, paralyzed
Senses: darkvision 60 ft., tremorsense 30 ft., passive Perception 16
Languages: understands Aquan but cannot speak
Challenge: 12 (8,400 XP)

---

Traits

Amphibious. Liopleurodon can breathe both air and water.

Keen Smell. Advantage on Wisdom (Perception) checks that rely on smell.

Predatory Instinct. Advantage on attack rolls against creatures that have not yet acted in combat.

---

Actions

Multiattack. Liopleurodon makes two attacks: one with its Bite and one with its Tail.

Bite. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 36 (4d12 + 6) piercing damage. If the target is a creature, it must succeed on a DC 18 Strength saving throw or be grappled (escape DC 18).

Tail. Melee Weapon Attack: +10 to hit, reach 15 ft., one target. Hit: 21 (3d8 + 6) bludgeoning damage.

Swallow. Liopleurodon makes one Bite attack against a Medium or smaller target it is grappling. If the attack hits, the target is swallowed, and the grapple ends. The swallowed target is blinded and restrained, has total cover against attacks outside Liopleurodon, and takes 21 (6d6) piercing damage at the start of each of Liopleurodon’s turns. Liopleurodon can have only one creature swallowed at a time.

---

Reactions

Tail Sweep. When a creature the Liopleurodon can see enters a space within 10 ft. of it, it can make a Tail attack against that creature.

---

Legendary Actions (3/turn)

• Lunge. Liopleurodon moves up to half its swim speed toward a target without provoking opportunity attacks.
• Bite Attack. Liopleurodon makes a single Bite attack.
• Tail Attack. Liopleurodon makes a single Tail attack.

---

Tactics

Liopleurodon is a patient ambush predator. It hides in deep water, waits silently, and strikes with sudden lunges and powerful bites. It prefers to grapple and swallow prey but uses its Tail to control space or fend off multiple attackers. It adapts to threats by retreating to deeper water if outmatched, relying on stealth and underwater mobility rather than magical or exaggerated abilities.

Liopleurodon

Huge animal (aquatic)
CR 9 • XP 6,400
N Huge animal (aquatic)

---

DEFENSE

AC 20, touch 11, flat-footed 18
(+2 Dex, +9 natural, –1 size)

hp 152 (16d8+80)

Fort +12, Ref +10, Will +6

Defensive Abilities hold breath
Weaknesses out of water

---

OFFENSE

Speed swim 60 ft. (cannot move effectively on land)

Melee bite +22 (3d6+12 plus grab)

Space 15 ft.; Reach 10 ft.

Special Attacks capsize, death roll, ferocious bite, grab, swallow whole (AC 17, 18 hp)

---

STATISTICS

Str 23 (+6), Dex 16 (+3), Con 21 (+5), Int 3 (–4), Wis 14 (+2), Cha 7 (–2)

Base Atk +12; CMB +19 (+23 grapple); CMD 30 (can’t be tripped)

Feats Great Fortitude, Improved Initiative, Lightning Reflexes, Skill Focus (Stealth), Power Attack, Toughness, Weapon Focus (bite), Improved Natural Attack (bite)

Skills Perception +16, Stealth +10 (+18 in water); Racial Modifiers +8 Stealth in water

Languages —

---

ECOLOGY

Environment temperate oceans
Organization solitary
Treasure none

---

SPECIAL ABILITIES

Capsize (Ex)

A Liopleurodon can overturn Large or smaller boats by ramming from below. It makes a Strength check against the vessel’s CMD, automatically succeeding against small craft such as rowboats.

Death Roll (Ex)

When it maintains a grapple on a Medium or smaller target, the Liopleurodon twists violently, dealing 3d6+18 additional damage and automatically maintaining the grapple.

Ferocious Bite (Ex)

Its crushing jaws grant a +4 bonus on bite critical confirmation rolls, and its bite has a ×3 critical multiplier.

Hold Breath (Ex)

The Liopleurodon can hold its breath for 126 rounds (about 12.5 minutes) but cannot breathe air.

Out of Water (Ex)

On land the creature can only move 5 feet as a full-round action, takes 1d6 nonlethal damage each minute, becomes fatigued after 5 minutes and exhausted after 10, and eventually begins to suffocate.

Swallow Whole (Ex)

It can swallow Medium or smaller creatures, dealing 2d6+6 bludgeoning damage and 2d6 acid damage each round. The interior has AC 17 and 18 hp.

---

TACTICS

Before Combat

The Liopleurodon approaches from below or behind, using depth and water distortion to conceal its advance.

During Combat

It opens with a decisive bite and grab, followed by an immediate death roll. Smaller or solitary targets are eaten quickly, while larger groups risk being scattered if it capsizes their vessel. It prefers quick, brutal engagements and avoids prolonged fights with heavily armored foes.

Morale

If reduced below 30 hp, it withdraws into deep water and attempts to escape.

Liopleurodon

Enormous creatures that can swim with unnerving grave. They are air breathers and so must surface occasionally for air. They often lurk near shorelines.

Originally Posted by demiurge1138 of the En World forums.

On this Thread

The largest creature in the prehistoric ocean, the lioplureodon is a short-necked plesiosaur supremely adapted to hunting other aquatic reptiles. A liopluerodon resembles a mammoth reptilian whale over eighty feet long. Its four wing-like paddles stretch over twenty feet long, and its head composes about one third of its body length.

---

Lioplureodon
Colossal animal (Aquatic)
Hit Dice	20d8+ 200 (290 hp)
Initiative	+5
Speed	Swim 40ft
AC	19 (-8 size, +1 Dexterity, +16 natural)
Base Attack/Grapple	+15/+48
Attacks	Bite+24 melee, 2 fin slaps +22 melee
Damage	Bite 4d8+17 (19-20 x2), fin slap 2d6+8 (19-20 x2)
Face/Reach	40ft/15ft
Special Attacks	Improved grab, swallow whole
Special Qualities	Blindsight 120ft
Saves	Fort +24, Ref +13, Will +9
Abilities	Strength 45, Dexterity 13, Constitution 30, Intelligence 2, Wisdom 16, Charisma 6
Skills	Hide +9, Move Silently +15
Feats	Great Fortitude, Improved Critical (bite, fin slap), Multiattack, Skill Focus (Move Silently) Weapon Focus (bite, fin slap)
Climate/Terrain	Warm or temperate ocean
Organization	Solitary or pair
CR	11
Treasure	None
Alignment	Always neutral
Advancement	21-60 HD (Colossal)

Combat

Surprisingly Stealthy for a creature of its size, a liopluerodon prefers to ambush its prey from below, grabbing it in their massive jaws, shaking it violently, and then swallowing the still living creature for digestion. They are fiercely territorial, and will attack any intruders, such as ships, without provocation.

Blindsight (Ex) Utilizing echolocation, a liopluerodon can discern objects and creatures within 120 feet. It does not usually need to make Spot or Listen checks to notice creatures within the range of its Blindsight. If deafened, or within the radius of a silence spell, the liopluerodon has to rely on it weak vision (maximum range 60 feet)

Improved Grab (Ex) Whenever a liopluerodon hits an opponent of Huge or smaller size with its bite attack, it can make a grapple check without receiving an attack of opportunity (grapple bonus +48). It can choose to conduct the grapple normally, or to only hold its opponent in its jaws (-20 penalty to grapple checks, but the liopluerodon is not considered grappled). A grappled creature takes bite damage every round, and the liopluerodon can choose to swallow its foe whole.

Swallow Whole (Ex) By making a successful grapple check, a liopluerodon may swallow a held foe whole. Once swallowed, a victim takes 2d8+10 points of bludgeoning damage plus 3d6 acid damage every round until it escapes or dies. A successful grapple check allows the creature to Climb out of the stomach and into the lioplurodon’s mouth, where another grapple check is required to get free.

Alternatively, the swallowed creature can escape by cutting its way out with either claws or a light slashing or piecing weapon. Dealing at least 50 points of damage (AC 20) in this fashion allows the creature to escape. Once a single swallowed creature exits, muscular action closes the whole; another swallowed creature must cut its way out as well. A liopluerodon’s stomach can hold 2 Huge, 4 Large, 16 Medium-sized, 32 Small or 64 Tiny or smaller creatures.

Skills A liopluerodon receives a +4 racial bonus to all Move Silently checks.