Mega Man 2: The Power Fighters

Mega Man 2: The Power Fighters, known in Japan as Rockman 2: The Power Fighters (ロックマン２ ザ パワーファイターズ), is a fighting game released for arcade. The player can choose Megaman, Proto Man, Bass or Duo to play with.

This game is in the continuity of Mega Man: The Power Battle, and both games where released together in Rockman Power Battle Fighters and Mega Man: Anniversary Collection for PlayStation 2, and Rockman Battle and Fighters for Neo Geo Pocket Color.

Story
It's a disaster: Doctor Light's lab has been attacked by Doctor Wily, and stolen some crucial parts for robots. And, if it weren't bad enough already, he has taken Roll as a hostage! Mega Man and Proto Man go to stop Wily, and stumble upon Duo, a big alien robot, who is willing to help. And, Bass is still angry that Wily has revived more Robot Masters, and teams up with the good side to destroy the enemies...

Bosses
and Wily Machine.

Trivia

 * In Bass' ending, Dr. Wily shows the plans from a new robot he is developing, and it looks very familiar to a certain robot with long hair...