This spell creates a magical, glowing swarm of gnats that appear around the target. The gnats fill a 5-foot emanation around the target, and seek to kill vermin. There are 2 gnats for every caster level you possess.
Mindless, non-magical vermin (mosquitoes, fleas, etc.) will not enter the emanation. A vermin who willingly enters the emanation is attacked by as many gnats as it has hit dice, each gnat dealing 1d4 damage. If a vermin exits and re-enters the emanation, a new set of gnats will attack it. If the vermin are in a swarm themselves (having the swarm subtype), every gnat converges on it, dealing 1d6 damage apiece. However, if you force the barrier against a vermin, the gnats will not attack it as long as it remains inside.
If the target of the spell is a vermin, it is unaffected by the swarm.
The spell ends when the duration expires, you dismiss it, or after all the gnats have attacked.
Material component: A gnat (or head of a gnat), impaled on a small shaft of wood.