Rollin' 22

Rollin' 22 (ローリン２２) is a gun enemy in Mega Man Zero 2 that can be as difficult to destroy as Seal Cannon, as they tend to shoot at ZeroXorZ and then flip down under pipes to evade Zero's fire. To make things even more complicated, the pipes are very slippery. They appear in Poler Kamrous' stage, the Computer Zone.