Undeath to Death

Caster Level(s): Wizard / Sorcerer 6, Cleric 6
Innate Level: 6
School: Necromancy
Descriptor(s): Negative
Component(s): Verbal, Somatic
Range: Medium
Area of Effect / Target: Colossal
Duration: Instantaneous
Additional Counter Spells:
Save: Will negates
Spell Resistance: Yes

This spell slays 1d4 HD worth of undead creatures per caster level (maximum 20d4). Creatures with the fewest HD are affected first; among creatures with equal HD, those closest to the point of origin of the burst are affected first.