Toxic Sludge (5e Creature)
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Medium ooze, unaligned
Skills Perception +4
Charge. If the toxic sludge moves at least 15 feet straight toward a target and then hits it with a Bite attack on the same turn, the target takes an extra 4 (1d8) bludgeoning damage.
Toxic Body. A creature that touches the toxic sludge takes 5 (1d10) poison damage (already included in melee attacks).
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 3) piercing damage plus 5 (1d10) poison damage. If the target is a creature, it must succeed on a DC 15 Constitution saving throw or be poisoned for 1 minute. A creature can repeat this save at the end of each of its turns, ending the effect on itself on a success.
Distantly related to the common slime, the toxic sludge takes down its prey with potent toxins and a disarmingly toothy smile.