Life For Life (3.5e Sacrifice)
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The Gate is mastery over death, and life. Through sacrifice, life may be restored. This sacrifice power has two forms. The first allows the caster to burn hp, and with a touch restore twice that amount to another. If he uses 15 hp, the target heals 30 hp. He may never use this power on himself, nor may he drop below 1 hp using this power.
It's other form is more sinister for what it does. It duplicates the effects of a Resurrection spell. However, the material cost may be cut in half if a sacrifice of blood is made. For every HD the body possessed, an equal amount of HD of living creatures must be sacrificed in a ritual lasting at least 10 minutes. Using Resurrection in this manner cuts costs (and perhaps reduces the enemy numbers) but gives the spell the [Evil] descriptor. Interestingly enough, undead may be restored by this ability, back to their undead states.
Health Cost (Healing): Variable.
Health Cost (Ritual): -13 and material components.