The Infiltrator 15z9 is a Boss in Co-op mode. This is one of the most dangerous bosses in co-op, kill him quick or you are in trouble! He is very precise with his weapon and the beams deal great damage. Rapid destruction is strongly advised, otherwise get behind cover/keep moving; never stand in one spot oh he will swipe away 1/3 of your health in a flash.
Infiltrator 15z9 uses the Infiltrator Armor Rig with what appears to be an 8Bit skin.(Great targeting).
Infiltrator 15z9 uses a Vaporizer.(Very powrfull).