Brown

Brown is a shelled robot in Mega Man 6 and it mainly appears in Knight Man's stage. It looks like a jar with lights on it and it shoots out from the jar. Shoot the jar when close, and its Met-like head will appear. Shoot the head to defeat the enemy. Octone from Mega Man 9 acts similarly to it. If you use a charge shot from the Power Adapter you can take it out in one hit without having to have it's head exposed.