Onomatopoeia

Onomatopoeia is a serial killer who targets non-powered, vigilante superheroes. He earned his name because he imitates noises around him, such as dripping taps, gunshots, etc. It seems that he may be able to perfectly imitate these sounds but that has been left ambiguous. He invariably carries two semiautomatic handguns and an army knife, and is a skilled unarmed combatant.

Appearances

 * Detective Comics 1