19 (natural armor)
296 (16d20 + 128)
0 ft., swim 50 ft.
Perception +8
bludgeoning, piercing, and slashing from nonmagical attacks
charmed, frightened, prone
darkvision 120 ft.
-
15
The sea serpent does double damage to objects and structures.
The sea serpent can breathe only underwater.
The sea serpent makes one bite attack and one constrict attack.
Melee Weapon Attack: +14 to hit, reach 10 ft., one target. Hit: 42 (6d10 + 9) piercing damage.
Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 20 (2d10 + 9) bludgeoning damage, and the target is grappled (escape DC 18). Until this grapple ends, the creature is restrained. The sea serpent can grapple up to three Large or smaller creatures.
The sea serpent exhales a foul, poisonous gas in a 120-foot cone. Each creature in that area must succeed on a DC 18 Constitution saving throw or take 55 (10d10) poison damage and be poisoned until the start of its next turn. On a successful saving throw, the creature is immune to the sea serpent's breath for 24 hours.