Tarantula hawk. They are named this because they hunt tarantula, paralyze them with their stings, and then fly them back to somewhere and lay their eggs in them.
I mean, what happens when the eggs hatch isn't that bad. Tarantulas don't have the nerves to feel what's going on and they are long dead before the larvae finish snacking.
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Also: You don't want to know what happens when the eggs hatch