Coven Ants

Spider Climb. If the swarm has a Climb Speed, the swarm can climb difficult surfaces, including along ceilings, without needing to make an ability check.

Swarm Form. The swarm can occupy another creature’s space and vice versa, and the swarm can move through any opening large enough for a Tiny insect. The swarm can’t regain Hit Points or gain Temporary Hit Points.

Choreographed Casting. The Coven Ants must have at least half their hit points to cast spells; below that, their formations become too ragged. Spellcasting is a collective effort—hundreds of tiny limbs weave intricate sigils in the air.

Spellcasting. The Coven Ants are a 7th-level spellcaster. Their spellcasting ability is Intelligence (spell save DC 14, +6 to hit with spell attacks). They require no material components, substituting synchronized movement.

Bites. Melee Attack Roll: +3, reach 5 ft. Hit: 6 (2d4 + 1) Poison damage, or 3 (1d4 + 1) Poison damage if the swarm is Bloodied.

Mandible Swarm. Melee Weapon Attack: +6, reach 0 ft., one creature in the swarm's space Hit: 21 (6d6) Piercing damage, or 10 (3d6) Piercing damage if the swarm is Bloodied at half hit points or fewer.

Fireball Formation. (Recharge 5–6). The swarm erupts into a precise, spiraling sigil that detonates in flame. This functions as the fireball spell (spell save DC 14), but the explosion is accompanied by synchronized high-kicks and pirouettes in miniature.