Unspecified Damage
From Drunkapedia
A small number of creatures do Unspecified Damage, there is no life protection that can lessen this damage beyond Armor spells.
Umbral Rift hits your hand for 11 points of damage!
Creatures that do unspecified damage:
- Fist of the Depths (critical hits only)
- Spectral Wisp
- Umbral Rift