Corrupted Carrion Crawler Broodmother

Keen Smell. The Corrupted Carrion Crawler Broodmother has advantage on Wisdom (Perception) checks that rely on smell.

Spider Climb. The Corrupted Carrion Crawler Broodmother can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Brood Swarm. As a bonus action, the Corrupted Carrion Crawler Broodmother can create a swarm  that can occupy another creature's space and vice versa. The swarm can move through any opening large enough for a Tiny creature. The swarm can't regain hit points or gain temporary hit points. Only one swarm can be operative at any one time.

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

Tentacles. Melee Weapon Attack: +10 to hit, reach 10 ft., one creature. Hit: 8 (1d6 + 4) poison damage, and the target must succeed on a DC 15 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: 10 (2d4 + 6) piercing damage.

Broodswarm. Melee Weapon Attack: +6 to hit, reach 0 ft., one creature in the swarm's space. Hit: 7 (2d6) piercing damage, or 3 (1d6) piercing damage if the swarm has half of its hit points or fewer. The target must make a DC 12  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.

Prematurely hatched spawn emerge from within the Corrupted Carrion Crawler Broodmother hungering for sustenence.  Once released, they do not attack the Broodmother, but will move towards as many other living creatures as possible within range of their 20 feet of movement.