Unfathomable Spirit

Tiny undead, chaotic evil

Armor Class 5
Hit Points 161 (19d4 + 114)
Speed fly 40 ft.

1 (-5) 1 (-5) 22 (+6) 8 (-1) 16 (+3) 16 (+3)

Saving Throws Con +10
Condition Immunities blinded, charmed, deafened, frightened, exhaustion, grappled, incapacitated, paralyzed, petrified, poisoned, prone, restrained, stunned, unconscious
Senses blindsight 60 ft. (blind beyond this radius), passive Perception 14
Languages understands the languages of its past life but cannot speak
Challenge 10 (5,900 XP)
Proficiency Bonus +4


  • Between Life and Death. The unfathomable spirit is not fully formed on the Material Plane. It cannot be targeted by spells or attacks, and it cannot take damage except when possessing another creature.
  • Damage Transfer. When anything other than the unfathomable spirit does damage to a creature possessed by the unfathomable spirit, the damage is split evenly between the unfathomable spirit and the possessed creature.
  • Malleable Form. The unfathomable spirit can turn invisible at will or project an illusory form to any creature within 60 feet.
  • Turn Immunity. The unfathomable spirit is immune to effects that Turn Undead.


  • Withering Touch (Possessed Form). When the unfathomable spirit possesses a creature, that creature can make a Withering Touch attack. Melee Spell Attack: +8 to hit, reach 5??. one target. Hit: 17 (4d6 + 3) necrotic damage.
  • Possession (Recharge 6). One Humanoid that the unfathomable spirit can see within 5 feet of it must succeed on a DC 16 Charisma saving throw or be possessed by the spirit; the spirit then disappears, and the target is incapacitated and loses control of its body. The unfathomable spirit now controls the body but doesn’t deprive the target of awareness. The unfathomable spirit can’t be targeted by any attack, spell, or other effect, and it retains its alignment, Intelligence, Wisdom, Charisma, and condition immunities. It otherwise uses the possessed target’s statistics, but doesn’t gain access to the target’s knowledge, class features, or proficiencies. The possession lasts until the body drops to 0 hit points or the spirit ends it as a bonus action. When the possession ends, the spirit reappears in an unoccupied space within 5 feet of the body. The target is immune to this spirit’s Possession for 24 hours after succeeding on the saving throw or after the possession ends.
  • Punish (Possessed Form). The unfathomable spirit wracks the creature it possesses with necrotic energy. The possessed creature must succeed on a DC 19 Constitution saving throw or take 27 (5d10) necrotic damage. It takes no damage on a successful saving throw.
  • Soul Bellow (Recharge 6) (Possessed Form). The possessed creature emits a deep, unsetiling moan that ratiles those nearby. All creatures within 30 feet of the possessed creature that can hear must succeed on a DC 19 Constitution saving throw or suffer 45 (10d8) force damage, or half upon a success.


One of the most mysterious forms of Undead is the unfathomable spirit. This spirit resides on the border between the Material and Ethereal Plane, making it difficult to see—much less destroy.

In its spirit form, the unfathomable spirit cannot be damaged or targeted by magic in any way. This ghastly vapor is only semi-present on the Material Plane at any given time, except when it has possessed the form of a living being.

An unfathomable spirit is as much an illusion as it is a ghost. Often invisible, this spirit can also show itself in several incorporeal forms. Even more terrifying, an unfathomable spirit can appear in different forms to different people or even reveal itself only to a single member of an adventuring party at a time.

When an unfathomable spirit makes itself known to the living, it can do so in different ways. It might look like rolling fog, an apparition blinking in and out of existence, or a swarm of insects taking the rough shape of a Humanoid.

Section 15: Copyright Notice

Grizelda’s Guide to Ghost Hunting Copyright 2022 Scoundrel Game Labs; Author(s) T.A. Gray, Jeremy Forbing, Andrew Marquis, Darren Kenney, Sven Truckenbrodt, DMBen.

This is not the complete section 15 entry - see the full license for this page