Invocation Grade: Lesser
Equivalent Spell Level: 3rd
You can create an area of shadow (as the darkness spell) that is filled with bats (as the bat swarm, except the swarm fills every square occupied by the darkness). The hungry darkness is stationary. You are immune to the attacks of your own hungry darkness, but you are still subject to the effect of the darkness. The hungry darkness remains as long as you concentrate on it (like concentrating on a spell), plus 2 rounds thereafter. If the bat swarm is destroyed, the darkness disappears as well.
Source: Complete Arcane, page 134.