Hungry Shadows

School: Conjuration 
Level: Warlock 3 
Casting Time: 1 standard action 
Components: V, S 
Range: Close (25 ft + 5 ft/2 levels) 
Duration: Concentration + 2 rounds 
Saving Throw: none; Spell Resistance: no 
You create a miniscule breach into the Shadow Plane. The breach results in a small pool of shadowstuff that radiates in a 20-foot radius of the portal, darkening the area as a darkness spell. The breach also trails with it a swarm of Fine-sized creatures from the Plane, who fill the area of the spell. These nameless scavengers from the twisted forests of the Shadow Plane will attempt to eat any non-Shadow Planar denizen who cross their path. Through the casting of this spell however, the caster appears to be a denizen of the plane, and as such is immune to the attacks of the swarm, though not the darkness effect of the breach.
For the purposes of the spell, the swarm counts as a bat swarm (Bestiary 30), except the swarm is Fine-sized and fills the entire spell area. If the swarm receives enough damage to kill it, it ends the spell, dispelling the darkness.