Spine-frilled neck arching up from the water like a snake ready to strike, this ship-sized serpent hisses a challenge.
Environment: Any ocean
Organization: 1
Proficiency Score: +14
Gargantuan; Neutral/Independent; animal, aquatic, fish, mystical
Armor Class: 27 (+2 Dex, +5 Natural, -4 Size, +14 Proficiency)
Hit Points: 225 (15d10+75)
Speed: 20 feet, Swim 60 feet
Initiative: +2 (advantage)
| STR | DEX | CON | INT | WIS | CHA |
| 18 (+4) | 14 (+2) | 21 (+5) | 2 (–4) | 11 (+0) | 11 (+0) |
Saves:
- Fortitude +19
- Reflex +16 (advantage)
- Will +14
+1d6 against effects with the magical or supernatural tags
Skills:
- Athletics +18 (advantage)
- Perception +14
- Stealth +16 (double advantage)
Advantage on Combat Maneuvers to Shove
Immunities:
- Effects with the cold tag
Resistances:
- 30 against effects with the fire tag
Senses: Passive Perception 24, dark vision 120 feet, constant Nondetection
Languages: Sylvan
Elusive. While in water, a Sea Serpent does not leave any trace of its passing, unless intentionally.
Hold Breath (-). A Sea Serpent never risks drowning.
Legendary Actions (1). A Sea Serpent can use one extra action per round. This action can be spent at any point in the round directly after a creature’s turn ends and another begins.
Many Appendages (2). A Sea Serpent has 1 bite and 1 tail and can Grab a creature with each, such that it can have up to 2 creatures Grabbed at a time.
Underwater Fighter. A Sea Serpent ignores penalties to bludgeoning damage underwater.
Actions
Bite. Melee Strike +18/+13/+8 (reach 15 feet, unarmed, versatile bludgeoning) with 5d8+4 piercing damage and inflicts the Grabbed condition (DC 29).
Constrict. As part of the same action to maintain the Grabbed condition, a Sea Serpent can constrict and inflict 2d8+6 bludgeoning damage.
Powerful “Stance”. As a Single Action, a Sea Serpent can take a stance and gain a 1d8 Insight bonus on melee damage rolls.
Swallow Whole. As a Single Action, a Sea Serpent can attempt to swallow a creature it has currently Grabbed by a bite attack. This is an Athletics check against the target’s Passive Athletics. If it succeeds, it swallows the target, inflicting Bite damage in the process. Each round after being swallowed, the target automatically takes 1d8+6 acid damage. The swallowed target is considered to still have the Grabbed condition, while the Sea Serpent is no longer considered to have a creature Grabbed. A swallowed target can try to cut its way free with any weapon that is 1 bulk or less and deals slashing or piercing damage or can try to escape the Grabbed condition with double disadvantage like trying to climb back out. The Sea Serpent’s stomach has AC 22 and 22 damage is required to cut an escape out of its stomach. If a swallowed target cuts its way out, the Sea Serpent cannot use the Swallow Whole ability for two rounds. If a swallowed target escapes through overcoming the Grabbed condition, it is treated as being back in the Sea Serpent’s mouth where it must spend an action jumping out or it will be in danger of another Bite attack and being Swallowed Whole again.
Tail. Melee Strike +18/+13/+8 (reach 20 feet, unarmed) with 4d8+6 bludgeoning damage and inflicts the Grabbed condition (DC 29).
Equipment
- Incidental