Ear Worm/Video Games/Mega Man

I can't beat Air Man, Okkusenman, and this other song by a Japanese music group lamenting the frustration factors of Elec Man/Guts Man's stages, as well as the Yellow Devil's attack pattern. The first and third ones mentioned above were both made by Team Nekokan.
Kuria Made wa Nemuranai (No Sleep Until Clear!) is the name of the song about three of the factors that made the first Mega Man 1 game so Nintendo Hard, and Team Nekokan, the band who made this, also has a couple of versions of Airman Ga Taosenai as well.
The original Mega Man's ((BROKEN))Cut Man's Stage music.
The opening music from Mega Man 2. Guess which song they use for the main menu of the Anniversary Collection.
- Flash Man's theme.
- Dr. Wily's themes, stage 1 and 2, in 2.
Gemini Man's theme from Mega Man 3.
- Shadow Man's theme
Mega Man 4's final boss theme.
Mega Man 9's Galaxy Man's theme is pretty catchy.
For more modern games, Sheep Man from Mega Man 10 gets stuck in your ear.
- And a particularly nasty Mega Man earworm, DEEP IN SPACE - WILY STAGE 5, which is also from Mega Man 10.
From the Mega Man X series, Boomer Kuwanger and Flame Stag's stages.
- As X bosses go, Crystal Snail is pretty obscure and a bit silly. The music, though, will sneak up on you at the worst times.
Ear worm songs from the Mega Man Battle Network series: Internet theme for BN3, the secret area music, and the opening theme
Area B of Mega Man ZX. Short level, memorable music.
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