Keen Smell. The carrion crawler has advantage on Wisdom (Perception) checks that rely on smell.

Spider Climb. The carrion crawler can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Multiattack. The carrion crawler makes two attacks: one with its tentacles and one with its bite.

Tentacles. Melee Weapon Attack: +8 to hit, reach 10 ft., one creature. Hit: 4 (1d4 + 2) poison damage, and the target must succeed on a DC 13 Constitution saving throw or be poisoned for 1 minute. Until this poison ends, the target is paralyzed. The target can repeat the saving throw at the end of each of its turns, ending the poison on itself on a success.

Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 7 (2d4 + 2) piercing damage.