Death knell

Death knell is a necromancy spell that finishes off a dying subject and saps his energy to strengthen the caster.

Effect
You draw forth the ebbing life force of a badly wounded creature and use it to fuel your own power. Upon casting this spell, you touch a living creature with -1 hit points or lower. If the subject fails its saving throw, it dies, and you gain 1d8 temporary hit points and +2 Strength. Additionally, your effective caster level goes up by +1, improving spell effects dependent on caster level. (This increase in effective caster level does not grant you access to more spells.) These effects last for 10 minutes per HD of the target creature.