Mega Man 4: Mega Man 4 - Ridley X Hack 6 (Dr. Cossack's Revenge)

Mega Man 4: Ridley X Hack 6 (Dr. Cossack's Revenge) is a fan-made modification of the original Mega Man 4 for the Nintendo Entertainment System. This hack features completely revamped levels, enemies, and bosses, offering a heightened challenge compared to typical Mega Man titles. Players navigate through unique stages that test their skills and abilities in new ways.