You all just want more gore than games provide already.
I'd like a mechanical boomerang crossbow/cannon type device that can shoot one or more triple-pointed boomerangs and catch them again on the return. Infinite ammo, outbound and return damage and some slicing action to boot. It would last through the whole game, and could be modified with different boomerangs and modules that might envelop them in fire or plasma etc.
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