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Colliatur Monstrosity

Gargantuan monstrosity, neutral

Though it is supremely rare, sometimes Udødelig’s tailored bacteria don’t help a creature defend against the colloid’s extraterrestrial influence, exacerbating its touch instead. The afflicted victim transforms and mutates into a thing of crystal shards, growing massively in size to as its mind fractures into a thousand irretrievable pieces. Driven by an instinctive hunger, it destroys and absorbs all the life around it before disappearing into the stars above.

Armor Class 20 (natural armor)
Hit Points 310 (20d20 +100)
Speed 40 ft.

24 (+7) 10 (+0) 20 (+5) 3 (–4) 10 (+0) 1 (–5)

Damage Vulnerabilities radiant
Damage Immunities piercing, poison, psychic, radiant, slashing, bludgeoning damage from nonmagical weapons that aren’t adamantine
Damage Resistances necrotic
Condition Immunities blinded, charmed, deafened, frightened, paralyzed, petrified, poisoned, prone, stunned
Senses darkvision 120 ft., passive Perception 10
Languages understands the languages it knew before the transformation, but can’t speak
Challenge 20 (25000 XP)

Special Traits

  • Absorb Magic. As a bonus action, the colliatur monstrosity targets any creature, object, or magical effect within 20 feet of it. The colliatur monstrosity chooses a spell already cast on the target. If the spell is of 3rd level or lower, the colliatur monstrosity absorbs the spell and it ends. If the spell if of 4th level or higher, the colliatur monstrosity must make a check with a +8 modifier. The DC equals 10 + the spell’s level. On a successful check, the colliatur monstrosity absorbs the spell and it ends. The colliatur monstrosity’s body emits scintillating patterns of light when it absorbs a spell, as if under the effects of a light spell. A colliatur monstrosity can only hold one absorbed spell at a time.
  • Crystalline Armageddon. When the colliatur monstrosity dies, it detonates in a cascade of crystalline shrapnel and searing light. Each creature within 60 feet of it must make a DC 19 Dexterity saving throw, taking 35 (10d6) slashing and 35 (10d6) radiant damage on a failed save, or half as much damage on a successful one. For every 10 Hit Dice worth of souls a colliatur monstrosity has currently stored via its soul destruction feature, the damage of this explosion increases by 7 (2d6) slashing and 7 (2d6) radiance.
  • Immutable Form. The colliatur monstrosity is immune to any spell or effect that would alter its form.
  • Magic Resistance. The colliatur monstrosity has advantage on saving throws against spells and other magical effects.
  • Magnitude. The mere approach of a colliatur monstrosity reverberates through the earth. In any round a colliatur monstrosity has taken an action, all non-flying creatures within 120 feet of it must succeed a Dexterity saving throw (DC 19) or fall prone.
  • Mighty Frame. A colliatur monstrosity can carry and lift tremendous weights due to their dense, crystalline frames. A colliatur monstrosity can lift and manipulate twice as much weight as usual for its Strength.
  • Soul Destruction. Mindless hunger for the souls of the slain drive the colliatur monstrosity ever onwards. Creatures slain within 100 ft. of the colliatur monstrosity have their souls drawn into the refracting crystals of the best. Only a true resurrection or direct divine intervention can bring the slain back to life. A colliatur monstrosity loses all stored souls after 24 hours or after completing a long rest, whichever comes first. Upon having consumed 200 Hit Dice of souls within a 24 hour period, the colliatur monstrosity gains a flying speed of 60 feet and may use this to travel even through the great beyond between the stars. The flying speed is lost after a long rest or upon entering a new planet’s magosphere, whichever happens first.


  • Multiattack. The colliatur monstrosity makes two melee attacks.
  • Slam. Melee Weapon Attack: +13 to hit, reach 15 ft., one target. Hit: 20 (3d8+7) bludgeoning damage.
  • Release Spell. The colliatur monstrosity can release an absorbed spell effect as a blast of prismatic energy, which blasts out as a sphere centered on the colliatur monstrosity with a radius of 10 feet per level of the absorbed spell. All creatures in the area of effect other than the colliatur monstrosity take 7 (2d6) radiant damage per level of the absorbed spell, or half damage with a successful DC 19 Dexterity saving throw. Creatures that fail the saving throw are also blinded until the end of the colliatur monstrosity’s next turn. Colliatur are immune to the harmful effects of this ability.
Section 15: Copyright Notice

Underworld Races and Classes © 2017 AAW Games LLC; Designers: Thilo Graf and Mike Myler