Swarm of Hiding Sea Horses

Large swarm of Small beasts, unaligned

Armor Class 12
Hit Points 49 (9d10)
Speed 0 ft., swim 20 ft.

14 (+2) 14 (+2) 10 (+0) 1 (-5) 10 (+0) 2 (-4)

Damage Resistances bludgeoning, piercing, slashing
Condition Immunities charmed, frightened, grappled, paralyzed, petrified, prone, restrained, stunned
Senses blindsight 30 ft., passive Perception 10
Challenge 2 (450 XP)
Proficiency Bonus +2


  • Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny sea horse. The swarm can’t regain hit points or gain temporary hit points.
  • Underwater Camouflage. The swarm has advantage on Dexterity (Stealth) checks made while underwater.
  • Water Breathing. The swarm can breathe only underwater.


  • Ram. Melee Weapon Attack: +4 to hit, reach 0 ft., one target in the swarm’s space. Hit: 20 (4d8 + 2) bludgeoning damage, or 11 (2d8 + 2) bludgeoning damage if the swarm has half of its hit points or fewer.
  • Tail Grasp. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 24 (5d8 + 2) bludgeoning damage. The target is grappled (escape DC 12) if it is a Large or smaller creature. Until this grapple ends, the target is restrained. The swarm can grapple no more than two targets at a time.
  • Ink Cloud (Recharge 5-6). A 15-foot-radius cloud of ink extends all around the swarm if it is underwater. Each creature in the area must make a DC 12 Dexterity saving throw. On a failed save, a creature takes 9 (2d8) acid damage, or half as much damage on a successful one. The area is heavily obscured for 1 minute, although a significant current can disperse the ink. After releasing the ink, the swarm can use the Dash action as a bonus action without provoking opportunity attacks.


A hiding sea horse is a shy, skittish creature that tends to swarm together in herds for additional protection. Its dark blue skin makes it challenging to spot underwater, but even more so amidst the ice of the arctic regions it sometimes calls home. A hiding sea horse assumes unfamiliar creatures are threats and will first attempt to flee or hide before attacking if there appears to be no escape. Hiding sea horses have an uncanny ability to detect youth in other creatures and have been known to play peekaboo with merfolk children.

Section 15: Copyright Notice

Affinity Torus Copyright 2022 Dias Ex Machina Author Chris Dias

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