Blood Healing

You recover 1 HP or 1 FP (your choice) when you first touch the corpse of a (formerly) living, bleeding creature with IQ 6+ that you, personally, have killed. You could slaughter 20 elves and move from one to the next, healing 20 HP. You’d get just 1 HP from even the biggest dragon, though – and nothing from angels, golems, zombies, etc.