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Sea Serpent

Sea Serpent CR 12

Spine-frilled neck arching up from the water like a snake ready to strike, this ship-sized serpent hisses a challenge.

XP 19,200
N Gargantuan magical beast (aquatic)
Init +4; Senses darkvision 120 ft., low-light vision; Perception +17


EAC 27; KAC 29
Fort +15, Ref +15, Will +11
Defensive Abilities elusive; Immunities cold; Resistances fire 30;


Speed 20 ft., swim 60 ft.
Melee bite +28 (3d6+25 P plus grab) or tail slap +21 (3d6+25 B plus grab)
Space 20 ft.; Reach 20 ft.
Offensive Abilities capsize, constrict (3d6+25 B), swallow whole


Str +9, Dex +4, Con +5, Int -4, Wis +0, Cha +0
Skills Athletics +21, Stealth +17, Survival +17
Languages none


Capsize (Ex)

A sea serpent can attempt to capsize a boat or ship of its size or smaller by ramming it as a charge attack and making a combat maneuver check. The DC of this check is 25 or the result of the boat captain’s Profession (sailor) check, whichever is higher.

Elusive (Su)

Sea serpents have long been the stuff of maritime legends, but despite countless attempts to hunt them, they are rarely encountered unless they wish it. As a full-round action while in water, a sea serpent can move up to its run speed (300 ft.) without leaving any trace of its passing. An elusive sea serpent gains a +40 circumstance bonus to its Stealth check. In addition, except when in combat, a sea serpent is considered to be under the effects of a nondetection spell. Both of these spell effects are at caster level 20th and cannot be dispelled.


Environment any ocean
Organization solitary

Nearly every world with an ocean has tales of immense sea serpents, yet proof of these immense and elusive creatures is remarkably difficult to come by. Not only are oceans vast and true sea serpents rare, but these creatures are quite adept at both avoiding capture and destroying ships bent on such a daunting task. Although sea serpents are little more than animals, they possess about them an air of mysticism that even old salts and cynics are forced to admit quickens the heart and buoys (or sinks) the spirit. Reports of sea serpent sightings are just as likely to encourage travel as they are to cause panic among seafarers, as explorers and adventurers flock to the site in hopes of sighting such a legendary creature.

Typical sea serpents are 60 feet in length and weigh 4,500 pounds, but their upward size limit is unknown.

Section 15: Copyright Notice

Alien Bestiary (Starfinder) © 2018, Legendary Games; Lead Designer: Jason Nelson. Authors: Anthony Adam, Kate Baker, John Bennet, Eytan Bernstein, Robert Brookes, Russ Brown, Duan Byrd, Jeff Dahl, Robyn Fields, Joel Flank, Matt Goodall, Robert J. Grady, Jim Groves, Steven T. Helt, Thurston Hillman, Tim Hitchcock, Nick Hite, Daniel Hunt, Mike Kimmel Marshall, Isabelle Lee, Jeff Lee, Lyz Liddell, Jason Nelson, Richard Pett, Tom Phillips, Alistair J. Rigg, Alex Riggs, Wendall Roy, Mike Shel, Neil Spicer, Todd Stewart, Russ Taylor, Rachel Ventura, Mike Welham, George Loki Williams, Scott Young.