Amorphous Horror

Medium aberration, any

Armor Class 14 (natural armor)
Hit Points 127 (15d8 + 60)
Speed 30 ft., climb 30ft.

16 (+3) 10 (+0) 19 (+4) 10 (+0) 11 (+0) 7 (-2)

Saving Throws Wis +3
Skills Perception +3
Damage Immunities acid
Condition Immunities prone
Senses blindsight 30 ft., passive Perception 13
Languages any two languages
Challenge 5 (1,800 XP)
Proficiency Bonus +3


  • Amorphous. The amorphous horror can move through a space as narrow as 1 inch wide without squeezing.
  • Shapechanger. The amorphous horror can use an action or a bonus action to polymorph into a form that resembles its Small or Medium humanoid appearance before it became a horror. Its statistics are the same in each form. Any equipment it is wearing or carrying isn’t transformed. It reverts to its true Medium form if it dies.


  • Multiattack. The amorphous horror makes two slam attacks.
  • Slam. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 7 (1d8 + 3) bludgeoning damage and 9 (2d8) acid damage.


  • Split. When an amorphous horror that is Medium or larger drops below half its hit points but has at least 10 hit points, it splits into two new horrors. Each new horror has hit points equal to half the original horror’s, rounded down. New horrors are one size smaller than the original horror.


Abominable Experiment. In desperate times science and magic can progress by leaps and bounds, but such rapid advancement has its risks. Without proper precautions, experimenters or their subjects might be caught in forces beyond imagining and become twisted into something abominable. No two mishaps are alike, yet each of the misbegotten results is known as an aberrant horror.

Warped Flesh. Those who survive the uncontrolled transformation into aberrant horrors become living weapons. Some theories say the body sees the transmuting force as a threat and evolves defenses against it. Others believe that the accident triggers dormant bestial adaptations from the distant past. Whatever the reason, aberrant horrors are vicious combatants, armed with hardened claws, venomous spines, and other strange adaptations.

Section 15: Copyright Notice

Grim Hollow: The Monster Grimoire © 2021, Ghostfire Gaming Pty Ltd. Author: Shawn Merwin

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