Bloated zombie/doc

Explodes (loudly) when close to you leaving behind a poisonous cloud. Nearly harmless when you're outside (clouds disperse faster) and at the edge of the range. If you are a melee character, use rocks (or any type of throwing weapon) to kill it from a, preferably, large distance and negate the possibility of dying from poison. "When it dies, nothing in particular happens" is dubious given it explodes in gas.