Mega Man & Bass is a spin-off title in the original Mega Man series and was originally released exclusively in Japan on April 24, 1998 for the Super Famicom. Mega Man & Bass was ported to the Game Boy Advance (GBA) handheld in 2002 and was localized in North America and PAL regions the following year.

After defeating the evil Dr. Wily countless times, the robotic hero Mega Man is called into action once again when a powerful being known as King steals the blueprints to the creations of Dr. Wily and Dr. Light in order to create an army for robotic dominance over humans. Having learned of the threat, Mega Man's rival Bass decides to take matters into his own hands. The game is an action-platformer where the player advances by defeating bosses and acquiring their signature weapons. Mega Man & Bass lets the player choose between either of its titular characters, each of which plays differently than the other.