Deep One Halfbreed

Medium aberration, neutral evil

Armor Class 16 (natural armor)
Hit Points 60 (8d8+24)
Speed 30 ft.

16 (+3) 13 (+1) 16 (+3) 11 (+0) 14 (+2) 10 (+0)

Saving Throws Con +5, Wis +5
Senses passive Perception 12
Languages Low Atlantean, Kalayan
Challenge 3 (700 XP)


  • Amphibious The deep one halfbreed can breathe both air and water.


  • Maddening Stab. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 1d6+3 piercing damage plus 2d6 psychic damage, and the target has tactical disadvantage when making Intelligence or Wisdom checks or saves for one round.
  • Unsettling Whispers (Recharge 4+) The halfbreed whispers unknowable truths to those nearby. Each enemy within 5 feet of the halfbreed must make an Int save (DC 15) or take 4d6 psychic damage and become incapacitated for 1 minute. The target may attempt a new save at the start of each of its turns to end the condition.


The Deep One halfbreed is a product of humans mating with the Deep Ones, the aquatic servants of Cthulhu and other undersea entities. A halfbreed is born human, but as it matures it slowly takes on more and more characteristics of the Deep Ones, until the transformation is complete and the creature migrates completely into the sea.

The cultists of Cthulhu idolize the Deep Ones as beings who are one step closer to their master. As such, they also revere the halfbreeds, who in their minds represent the transformation they themselves have always desired.

Section 15: Copyright Notice

Primeval Thule Campaign Setting Copyright 2021 Sasquatch Game Studio, LLC. Design Richard Baker, David Noonan, Stephen Schubert

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