Sea Serpent, Brine

Sea Serpents

The sea serpents, great snakelike creatures that have roamed the oceans for ages, are nearly as old as the dragons that roam the sky. Unlike dragons, these great, scaly, serpentine beasts are products of natural evolution, though many scholars suspect magical influence, either deliberate or natural, somewhere in their evolution.

Sea serpents display great variation in size, color, intellect, and temperament. All of them, however, bear certain similarities. They are long, serpentine, warmblooded creatures that resemble snakes in appearance, though they also have two sets of flippers. On some sea serpents, these flippers are large and powerful, while on others they are so small and atrophied as to be almost unnoticeable. All sea serpents are aquatic, as their name implies, but they can survive for extended times out of water and some can even make their way about on land. Furthermore, all sea serpents are sentient, with intellects ranging from that of a smart dolphin to levels rivaling the smartest humans.

One trait that sea serpents share with dragons is a sense of innate superiority, a feeling that they are unequalled, unchallenged masters of the sea.

Unlike dragons, sea serpents are not distinguished by color or age. A few species are as acquisitive as dragons, but most have no interest in hoarding wealth or surrounding themselves with worshipful, lesser creatures. All sea serpents can speak and understand aquatic, and many know Draconic as well. The more intelligent among them often learn the languages of nearby marine civilizations or the languages of seagoing surface dwellers.

In combat, most sea serpents use similar tactics. All have venomous bites, and all have the ability to trap prey in their coils and crush the life out of them the way a giant constrictor snake does. The largest sea serpents can even crush ships this way; mariners in their smoky dens delight in recounting tales of horror about great serpents that splintered mighty hulls and then gulped down the helpless sailors as they splashed in the water or sank into the brine.

Because they are intelligent, sea serpents can often be reasoned with or bargained with, if the bargainer has something the sea serpent wants and approaches as a supplicant, not an equal. They are adaptable to circumstances and never throw themselves into battle rashly.

Sea Serpent, Brine

This serpentine creature is about 20 feet long from nose to tail, with two sets of large flippers and a body that’s somewhat wider side-to-side than top-to-bottom. A finned crest runs the length of its back. The body is dark blue with a lighter underbelly, often tinged with rust or green highlights, and the head is marked with notable, almost batlike ears.

Brine Sea Serpent

XP 5,900 ()

CE Huge ()

Initiative +2


AC 17 (natural armor)

hp: 168 (16d12 + 64)

Saving Throws: Dex +6, Con +8, Str +9

Immunity: Paralysis, prone, stun, unconsciousness


Speed: swim 60 ft.

Multiattack: A brine sea serpent attacks once with its tail and either bites or uses its brine blast.

Melee Attack—Bite: +9 to hit (reach 5 ft.; one creature). Hit: 2d10 + 5 piercing damage plus 2d6 poison damage, and the target must make a successful DC 17 Str saving throw or be grappled and restrained. If the target of this attack is already grappled by the sea serpent, the attack hits automatically but the target repeats the saving throw, escaping from the grapple and restraint if the save succeeds. A brine serpent can have one creature grappled at a time.

Melee Attack—Tail Slap: +9 to hit (reach 15 ft.; one creature). Hit: 2d8 + 5 bludgeoning damage and the target is pushed 10 feet away from the sea serpent.

Area Attack—Brine Blast (1/day): automatic hit (range 50-ft. cone; creatures in cone). Hit: 10d8 acid damage, or half damage with a successful DC 16 Dex saving throw.


Str 21 (+5), Dex 15 (+2), Con 18 (+4),

Int 7 (–2), Wis 13 (+1), Cha 14 (+2)

Languages: Aquan, Draconic

Skills: Athletics +9, Perception +5

Senses: Darkvision 60 ft.


The sea serpent can take up to three legendary actions per round. Legendary actions are taken at the end of another creature’s turn, and only one can be taken after each turn.

Coiling Maneuver: +9 to hit (reach 5 ft.; one creature). Hit: the target must make a successful DC 16 Str saving throw or be grappled and restrained by the sea serpent. A brine serpent can have one creature grappled at a time.

Concentrate Brine: The sea serpent can try to recharge its brine blast attack. Roll 1d6; the attack recharges on a roll of 5 or 6.

Tail Attack: The sea serpent uses its tail attack against a target within reach.


Environment: Any

Organization: Solitary

The brine sea serpent is an aggressive but relatively stupid (compared to other sea serpents) predator of the deeps. It is the only sea serpent able to attack in a manner similar to a dragon’s breath weapon. The brine sea serpent has a special organ that harvests sodium from seawater and stores it in concentrated form in a gland in its cheek. Unlike a dragon’s breath, this weapon takes an hour or more to recharge after it’s used, but the brine serpent can speed the process by gulping enormous quantities of seawater.

The brine serpent lives in a cave on the ocean floor, where it maintains a hoard, much as a dragon does. The brine serpent’s hoard is scavenged from sunken ships, so it often lives in seas known for their storm dangerous storms; besides the potential for treasure, storms also send tasty sailors sinking down into the brine serpent’s territory. A brine serpent will attack a ship directly if it is hungry enough.

The eyes of a brine serpent are small, but it possesses large ears that give it exceptional hearing. In quiet seas, it can detect sounds from many miles away.

Against lone prey, the brine serpent likely just rushes in and attack with its bite, saving the brine blast in case a bigger target becomes available. When confronting a group, it uses its brine blast first.