I'm picky, so I have to break it down by system.
Arcade -- Galaga
NES -- Super Mario Bros. 3
SNES -- Donkey Kong Country
GBC -- Harry Potter and the Chamber of Secrets
Genesis -- Sonic the Hedgehog 2
And if the N64 is considered retro, then I'd have to say Super Mario 64 for that system.
Arcade -- Galaga
NES -- Super Mario Bros. 3
SNES -- Donkey Kong Country
GBC -- Harry Potter and the Chamber of Secrets
Genesis -- Sonic the Hedgehog 2
And if the N64 is considered retro, then I'd have to say Super Mario 64 for that system.