Uncommon N Gargantuan Animal
Senses Perception +22; darkvision
Skills Acrobatics +18, Athletics +26 (+28 to Swim), Stealth +28
Str +8, Dex +4, Con +6, Int -4, Wis +2, Cha +0
Undetectable (abjuration, primal) A sea serpent automatically tries to counteract any detection, revelation, or Scrying divination attempted against it, using its Stealth modifier for its counteract modifier.
AC 35; Fort +25, Ref +21, Will +21
Speed 20 feet, swim 60 feet
Melee jaws +27 (reach 20 feet), Damage 3d10+14 piercing plus Grab
Melee tail +27 (agile, reach 30 feet), Damage 2d10+14 bludgeoning plus Grab
Ranged water spout +25 (brutal, range increment 100 feet, water), Damage 2d6+12 bludgeoning plus sea serpent algae
Capsize (attack) The sea serpent attempts to capsize an aquatic vessel of its size or smaller that it's adjacent to. It must succeed at an Athletics check with a DC of 35 or the pilot's Sailing Lore DC, whichever is higher.
Constrict 1d10+14 bludgeoning
Sea Serpent Algae (incapacitation, poison) The water in the ballast organs around the sea serpent's neck is full of psychotropic algae.; Saving Throw DC 34 Fortitude; Maximum Duration 6 rounds; Stage 1 confused and, if flying, spends its first action each turn to descend 20 feet (1 round); Stage 2 confused and, if flying, descends until reaching the ground or water below (1 round).
Spine Rake (attack, move) The sea serpent extends the spines along its back and Swims or Strides. Each creature the serpent is adjacent to at any point during its movement takes 4d6+8 slashing damage (DC 32 basic Reflex save).
Swallow Whole (attack) Huge, 2d10+6 bludgeoning, Rupture 20
These fabled beasts resemble massive snakes with long rows of finned spines down their back. Temperamental and territorial, sea serpents can capsize a boat with ease, and most won't hesitate to do so when hungry or threatened. Stories abound of aggrieved captains who spend their entire lives hunting down the elusive monster that sunk their ships and took their livelihoods. These hunts rely on rumors and glimpses of the beasts, as few survive the catastrophes wrought by sea serpents.
While many fishermen's tales paint sea serpents as divinely appointed guardians of the ocean or, alternately, as evil and demonic agents, the truth is that most sea serpents are simply very large beasts with a knack for avoiding magical detection.