Karts
Super Blooper: Get a gold trophy on the 50cc Leaf Cup.
Daytripper: Get a gold trophy on the 150cc Leaf Cup.
Sprinter: Beat all 32 staff ghosts by at least 7 seconds.
Bikes
Zip Zip: Get a gold trophy on the 100cc Lightning Cup.
Sneakster: Get at least a ★ ranking on the 100cc Mushroom, Flower, Star, and Special Cup.
Dolphin Dasher: Get a gold trophy on the MIRRORcc Star Cup.