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Soul-reaving aura
Type of feat: invocation
Prerequisite: warlock 2, charisma 12+
Specifics: This eldritch invocation puts a permanent aura around the warlock, each dead creature that enters the aura (once per creature), will give the warlock temporary hitpoints equal to it's HD for 1 round + 1 round for every 2 warlock levels.
Use: automatic.