Mosasaur

Family: Dinosaurs

Huge beast, unaligned

Armor Class 13 (natural armor)
Hit Points 145 (14d12 + 56)
Speed 10 ft., swim 40 ft.

STR	DEX	CON	INT	WIS	CHA
24 (+7)	10 (+0)	18 (+4)	2 (-4)	12 (+1)	7 (-2)

Senses passive Perception 11
Challenge 7 (2,900 XP)

SPECIAL TRAITS

• Hold Breath A mosasaur can hold its breath for up to 30 minutes.

ACTIONS

• Bite. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 4d10+7 piercing damage. If the target is a large or smaller creature, the mosasaur gains a bonus action to use its Swallow attack against the target.
• Swallow. Melee Weapon Attack: special, reach 0 ft., one Large or smaller creature hit by the mosasaur’s bite. The target must make a Str save (DC 18) or be swallowed by the mosasaur. A swallowed creature is blinded and restrained, and takes 4d6 acid damage at the start of each of its turns. It has total cover from attacks outside the mosasaur. If a mosasaur takes damage from a swallowed creature, it must make a Con save (DC equal to damage dealt) or regurgitate all creatures in its stomach. If the mosasaur dies, a swallowed creature can escape by using an action to crawl 10 feet back up its throat.

ABOUT

Inland seas are home to a variety of large, hungry marine predators, but none are feared as much as the terrible mosasaur. A throwback to a far-distant past when giant reptiles roamed all the oceans of the world, the mosasaur is thankfully rare in the present age. They have been known to sink galleys by ramming them beneath the waterline, then gorge themselves on a dozen or more of the surviving sailors as they struggle in the water. Mosasaurs have also been known to crawl ashore and attack coastal villages, although they are slow and clumsy on land.

Stocky and powerfully built, this great cat’s most salient feature is a pair of foot-long fangs jutting down from its upper jaw.

Section 15: Copyright Notice

Primeval Thule Campaign Setting Copyright 2021 Sasquatch Game Studio, LLC. Design Richard Baker, David Noonan, Stephen Schubert

Tylosaurus

“Mosasaur” – Surging out of the water, this massive lizard is shaped like a giant fish with a powerful, toothed maw.

This predatory marine lizard swims with four flippered limbs and a powerful, fluke-like tail. Its extended snout is filled with sharp teeth, and it feeds on both aquatic and surface prey. They are known to attack ships, mistaking them for basking whales or other creatures. A tylosaurus grows up to 50 feet in length and weighs 30,000 pounds.

Tylosaurus CR 8

XP 4,800
N Gargantuan animal
Init +1; Senses low-light vision, darkvision 60 ft.; Perception +14

DEFENSE

AC 20, touch 8, flat-footed 18 (+1 Dex, +1 dodge, +12 natural, –4 size)
hp 105 (10d8+60)
Fort +15, Ref +8, Will +4

OFFENSE

Speed 20 ft., swim 50 ft.
Melee bite +15 (2d8+18 plus grab)
Space 15 ft.; Reach 15 ft.
Special Attacks swallow whole (2d6+12 bludgeoning, AC 16, hp 10)

STATISTICS

Str 34, Dex 13, Con 22, Int 2, Wis 13, Cha 9
Base Atk +7; CMB +23 (+27 grapple); CMD 35 (39 vs. trip)
Feats Dodge, Cleave, Great Fortitude, Mobility, Power Attack
Skills Perception +14, Swim +20; Racial Modifiers +8 Swim

SPECIAL ABILITIES

Swallow Whole (Ex)

When a Tylosarus begins its turn with an opponent grappled in its mouth (see Grab), it can attempt a new combat maneuver check (as though attempting to pin the opponent). If it succeeds, it swallows its prey, and the opponent takes bludgeoning damage (2d6+12). A swallowed creature can escape by doing 9 points of damage to the inside of the Tylosarus with a light slashing or piercing weapon (AC 16). A creature that escapes the pin while swallowed whole emerges from the Tylosarus’s stomach, not its throat, where it may be grabbed and pinned again.

Tylosaurus Companions

Starting Statistics: Size Medium; Speed 20 ft., swim 50 ft.; AC +3 natural armor; Attack bite (1d6); Ability Scores Str 10, Dex 17, Con 10, Int 2, Wis 13, Cha 9; Special Qualities low-light vision, scent.

7th-level Advancement: Size Large; AC +2 natural armor; Attack bite (1d8 plus grab); Ability Scores Str +8, Dex –2, Con +4.

ECOLOGY

Environment warm aquatic
Organization solitary, pair, or school (3–6)
Treasure none

Section 15: Copyright Notice

Pathfinder Roleplaying Game Bestiary 2, © 2010, Paizo Publishing, LLC; Authors Wolfgang Baur, Jason Bulmahn, Adam Daigle, Graeme Davis, Crystal Frasier, Joshua J. Frost, Tim Hitchcock, Brandon Hodge, James Jacobs, Steve Kenson, Hal MacLean, Martin Mason, Rob McCreary, Erik Mona, Jason Nelson, Patrick Renie, Sean K Reynolds, F. Wesley Schneider, Owen K.C. Stephens, James L. Sutter, Russ Taylor, and Greg A. Vaughan, based on material by Jonathan Tweet, Monte Cook, and Skip Williams.

Tylosaurus

Huge beast, unaligned
Challenge: 8 (3,900 XP)
Proficiency Bonus: +3

Armor Class: 15 (natural armor)
Hit Points: 136 (13d12 + 52)
Speed: 40 ft., swim 60 ft.

STR	DEX	CON	INT	WIS	CHA
22 (+6)	14 (+2)	18 (+4)	5 (–3)	12 (+1)	8 (–1)

Saving Throws: Str +9, Dex +5, Con +7
Skills: Perception +4, Stealth +5
Senses: Darkvision 60 ft., passive Perception 14
Languages: —

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Traits

• Amphibious. The tylosaurus can breathe air and water.
• Keen Smell. The tylosaurus has advantage on Wisdom (Perception) checks that rely on smell.
• Swimmer’s Agility. The tylosaurus can move through water without impediment and can dash as a bonus action while swimming.

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Actions

Multiattack. The tylosaurus makes two attacks: one with its bite and one with its tail.

Bite. Melee Weapon Attack: +9 to hit, reach 15 ft., one target.
Hit: 32 (5d10 + 6) piercing damage. If the target is a creature, it must succeed on a DC 17 Strength saving throw or be grappled (escape DC 17). Until this grapple ends, the target is restrained, and the tylosaurus can’t bite another target.

Tail Slam. Melee Weapon Attack: +9 to hit, reach 10 ft., one target.
Hit: 24 (3d10 + 6) bludgeoning damage. If the target is grappled, it is also pushed 10 feet away and knocked prone.

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Legendary Actions

The tylosaurus can take 2 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature’s turn. The tylosaurus regains spent legendary actions at the start of its turn.

• Tail Sweep. The tylosaurus makes one tail slam attack.
• Swift Lunge (Costs 2 Actions). The tylosaurus moves up to half its swim speed without provoking opportunity attacks.

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Tactics

• The tylosaurus uses its swim speed and stealth to ambush prey from below, grappling them with its powerful bite.
• It uses tail slams to knock enemies prone and create distance when threatened.
• Swift lunges allow it to reposition quickly underwater to maintain pressure or escape danger.
• Prefers isolated targets but will fiercely defend its territory against rivals or intruders.

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Environment

Tylosaurus inhabits warm coastal waters, reefs, and open ocean where it rules as an apex predator, stalking fish, ammonites, and other marine reptiles.

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Treasure

Tylosaurus teeth and bones are sought after by coastal tribes and collectors, often fashioned into weapons, jewelry, or talismans.