Bad Fliers. The swarm falls at the end of a turn if it’s airborne and the only thing holding it aloft is its flying speed.

Swarm. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny abyssal chicken. The swarm can’t regain hit points or gain temporary hit points.

Multiattack. The swarm makes two attacks: one with its bites and one with its claws.

Bites. Melee Weapon Attack: +4 to hit, reach 0 ft., one target in the swarm’s space. Hit: 15 (6d4) piercing damage, or 7 (3d4) piercing damage if the swarm has half of its hit points or fewer.

Claws. Melee Weapon Attack: +4 to hit, reach 0 ft., one target in the swarm’s space. Hit: 21 (6d6) slashing damage, or 10 (3d6) slashing damage if the swarm has half of its hit points or fewer.