Win the Mirror Star Cup. How to Unlock Characters in Mairo Kart: Double Dash How to Unlock Toad and Toadette in Double Dash. He is an unlockable character, and, for unknown reasons, is a Heavyweight Class Character. Win the 50cc Mushroom Cup. creepier than ever! Win the 100cc Special Cup. Barrel Train (Diddy Kong's Kart) Finish the Star Cup in 150CC: Bloom Coach (Daisy's Kart) Finish the Flower Cup in 50CC: Boo Pipes (King Boo's Kart) Finish the Special Cup in Mirror Mode: Bullet Blaster (Bowser Jr.'s Kart) Finish the Special Cup in 50CC: Green Fire (Luigi's Kart… How to Unlock Karts in Mario Kart: Double Dash How to Unlock Green Fire in Double Dash. King Boo, the king of all the Boos (which are ghosts), comes to Mario Kart: Double Dash!! How to Unlock Petey Piranha and King Boo in Double Dash.