Fireball Fly Swarm (5e Creature)
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Fireball Fly Swarm
Fireball Burst. If the swarm suffers a critical hit from an attack that did not deal cold damage, one of the flies comprising the swarm erupts in a 5-foot radius ball of fire. Creatures in the area must make a DC 13 Dexterity saving throw, taking 7 (3d4) fire damage on a failure or half as much on a success.
Multiattack. The fireball fly swarm makes two attacks: one Bites, and one Suicide Dive (if it has less than maximum Hit Points)
Suicide Dive. If the swarm has less than maximum Hit Points, it can sacrifice one fireball fly. The swarm loses 2 Hit Points. The sacrificial fly strikes a point within 5 ft. of the swarm and erupts per Fireball Burst.
These insects are infused with elemental fire and can be found swarming in rocky wilderness areas, particularly near active volcanoes or magma streams. Like bees, individual fireball flies will sacrifice themselves to protect the swarm. They do so by immolating themselves in a burst of fire.
A fireball fly swarm is a variant swarm of insects (Monster Manual p. 338). Use the swarm of insects statblock with the following changes.