KIRBY'S DREAMLAND!!!! - that was my favorite. It also had different extensions like Adventure and Pinball.
My brother and the kids we used to babysit would have long Mario 3 tournaments. (We cheated, we used Game Genie.)
Excite bike - I used to make the most impossible courses. I think we just like making the guy fall down hills.
Tetris - as always
Mario Kart for n64
Mario Land or whatever for SNES
And arcade games... The SImpsons... my friends and I got to the Mr Burns level but didn't know what to do and we ran outta quarters
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