Necrotic Skull Bomb

Level: Wiz/Sor 5, Clr 5
School: Necromancy
Components: V,S
Casting Time: 1 Action
Range: Medium
Target: 20' Radius Blast
Duration: 1 hour per level
Save: Fort Negates
Spell Resist: Yes

You imbue a humanoid skull with negative energy and hurl it. Ths skull detonates on impact, releasing the negative energy contained within.All creatures in the blast gain 1d4 negative levels. Assuming the creature survives this drain, levels are regained after a number of hours equal to your caster level have passed.(Maximum 15 hours)
An undead creature in the blast gains 1d4 x 5 temporary Hit Points for 1 hour.