> Our most potent magics must be fueled by blood sacrifice. To lengthen and empower our spells, we will kill a small animal like a bird, mouse, frog, or rat and pour its life force into our spells. Of course, no decent feline would sacrifice a sapient animal.
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The corpse must be fresh—one sleep old or less—but it doesn’t have to be complete; you might like to bite the head and front parts off for a tasty snack before you get to work.