Melee Weapon Attack: +3 to hit, reach 0 ft., one target in the swarm's space. Hit: 10 (4d4) piercing damage, or 5 (2d4) piercing damage if the swarm has half of its hit points or fewer. The target must make a DC 12 Constitution saving throw, taking 14 (4d6) poison damage on a failed save, or half as much damage on a successful one.