Terror Slime (5e Creature)
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Gargantuan ooze, chaotic evil
Damage Vulnerabilities radiant
Amorphous. The slime can move through a space as narrow as 1 inch wide without squeezing.
Holy Susceptibility. If the contents of a flask of holy water are poured onto the slime, it takes 2d6 radiant damage, as though it were a fiend or undead.
Necrotic Aura. At the start of each of the slime's turns, each creature within 5 feet of it takes 10 (3d6) necrotic damage. A creature that touches the slime or hits it with a melee attack while within 5 feet of it takes 10 (3d6) necrotic damage.
Spider Climb. The slime can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Pseudopod Melee Weapon Attack: +10 to hit, reach 25 ft., one target. Hit: 15 (2d10 + 4) bludgeoning damage, plus 10 (3d6) necrotic damage. The target must succeed on a DC 19 Strength saving throw or be pulled to an unoccupied space within 5 feet of the ooze.
A terror slime is created when large amounts of energy from the negative energy plane leak into a mundane water source. These creatures are generally about as large as a house but can be hundreds of times larger. The bane of these oozes is holy water.