Heavy weapon dude

The Chaingunner (sometimes called Heavy weapon dude) is a new addition to Doom II. He is a former human who carries a chaingun which is dropped upon death and can be picked up by players. Although a chaingun is fired, the speed of fire by this enemy is slower than the speed of a player firing a chaingun, and the sound effect is that of the shotgun. When a chaingunner begins firing, he doesn't stop (he turns around very fast) until kills his target, his target leaves his line of sight or he is killed. Similar behavior can be observed with the Spider Mastermind and Arachnotron.

Internally the Doom source code gives the Chaingunner the type name MT_CHAINGUY. The sprites for the Chaingunner have the prefix CPOS.