Well, Act I is a Rock Opera, telling the story of Megaman's fight to free the people of his city, and avenge his fallen brother. Act II, is also a Rock Opera, though the musical styles vary more, based on the characters in the songs, which is sort of a prequel, detailing Light and Wily's relationship, and Wily's rise to power.

MVS - The Protomen is a remix album. Makeup and Vanity Set took songs from Act I and made bitmusic versions.
From Act I


From Act II


From Makeup and Vanity Set

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