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Mario Circuit 2 - Super Mario Kart
Ghost Valley 1 - Super Mario Kart
Bowser Castle 1 - Super Mario Kart
Koopa Troopa Beach - Mario Kart 64
Wario Stadium - Mario Kart 64
DK Jungle Parkway - Mario Kart 64
Most of all, where it all started; Mario Circuit 1 - Super Mario Kart
I was going to say DK Mountain...
However, I’m going to go with an outside-the-box (likely impossible) choice - how awesome would it be if they could include a level from Diddy Kong Racing (like Crescent Island or Darkmoon Caverns)?! Maybe it could help launch a much-needed sequel!
One can dream…