King Slime (5e Creature)
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Huge ooze, chaotic evil
Damage Vulnerabilities cold
Charge. If the slime moves at least 15 feet straight toward a target and then hits it with a pseudopod attack on the same turn, the target takes an extra 11 (2d10) bludgeoning damage.
Slippery. The slime has advantage on ability checks and saving throws made to escape a grapple.
Pseudopod. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 25 (4d10 + 3) acid damage, and the target is grappled (escape DC 14). Until this grapple ends, the creature is restrained, and the slime can't make pseudopod attacks against another target.
Swallow. The slime makes one pseudopod attack against a Medium or smaller target it is grappling. If the attack hits, the target is also swallowed, and the grapple ends. While swallowed, the target is blinded and restrained, it has total cover against attacks and other effects outside the slime, and it takes 21 (6d6) acid damage at the start of each of the slime's turns. A slime can have only one creature swallowed at a time.
A king slime is an incredibly dangerous variety of slime, able to swallow a human whole.
Ooze Nature. A king slime doesn't require sleep.