Large aberration, chaotic evil

Armor Class 16 (natural armor)
Hit Points 126 (12d10 + 60)
Speed 10 ft., swim 40 ft.

17 (+3) 14 (+2) 20 (+5) 12 (+1) 16 (+3) 18 (+4)

Saving Throws Con +8, Wis +6
Skills Perception +6
Damage Resistances cold
Senses darkvision 90 ft., passive Perception 16
Languages Aquan, Primordial
Challenge 6 (2,300 XP)


  • Water Breathing. The yavalnoi can breathe only underwater.
  • Innate Spellcasting. The yavalnoi’s innate spellcasting ability is Charisma (spell save DC 15). It can innately cast the following spells, requiring no material components.


  • Multiattack. The yavalnoi makes three attacks: one with its bite, one with its claw, and one with its tail.
  • Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 14 (2d10 + 3) piercing damage.
  • Claw. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 3) slashing damage.
  • Tail. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 10 (2d6 + 3) bludgeoning damage.
  • Luminous Burst (Recharge 5-6). The anchor-shaped organ atop the yavalnoi’s head emits a burst of blue light. Each hostile creature within 30 feet of the yavalnoi must succeed on a DC 15 Wisdom saving throw or be outlined in blue light for 1 minute. While outlined in blue light, a creature can’t breathe underwater. This effect dispels spells such as water breathing and temporarily suppresses water breathing granted through magic items or a creature’s natural physiology. In addition, the yavalnoi and creatures friendly to the yavalnoi have advantage on attack rolls against creatures outlined in blue light. A creature outlined in blue light can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
  • Call of the Deep (1/Day). The yavalnoi magically calls 2d4 giant crabs or 1 giant octopus. The called creatures arrive in 1d4 rounds, acting as allies of the yavalnoi and obeying its spoken commands. The beasts remain for 1 hour, until the yavalnoi dies, or until the yavalnoi dismisses them as a bonus action.


Rising up from the seafloor is a nightmarish creature resembling an obese mermaid with a wide, fluked tail, claws, and a humanoid head with a fish-like mouth and large, saucer-like, yellow eyes. An organ like the anchor of a boat emerges from its brow, shedding a pale blue light that glimmers off its iridescent crimson scales.

Monster Creator. Yavalnois are wicked aberrations capable of procreating with almost any creature from the sea, be it a sahuagin, giant crab, or even a kraken. The results of these unions vary. Most often the offspring is identical to the other parent, but sometimes it is another yavalnoi or something completely different, leading to many of the more aberrant creatures of the deep oceans.

Objects of Worship. Many intelligent evil sea creatures such as sahuagin and lesser scrags venerate yavalnois almost as if they were gods, guarding them and keeping them happy and fed. A yavalnoi is usually accompanied by several fawning sahuagin, scrags, or similar monsters willing to lay down their lives for it.

Section 15: Copyright Notice

Tome of Beasts 2. © 2020 Open Design LLC; Authors Wolfgang Baur, Celeste Conowitch, Darrin Drader, James Introcaso, Philip Larwood, Jeff Lee, Kelly Pawlik, Brian Suskind, Mike Welham.

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