If I didn't know better, I might think this game was designed by M.C. Escher. This time, your racer's car/bike has magnetic wheels that allow it to drive on roads that flip sideways and even upside-down!
Here are some screenshots that show off some of the places this ability can be used:
Spoiler:
The characters that have been confirmed for the game are: Mario, Luigi, Peach, Daisy, Bowser, Donkey Kong, Yoshi, Koopa Troopa, Toad, Toadette, Wario, and Waluigi. They haven't confirmed any new items for the game, but i suspect they may soon.
Sorry from bringing this post from the dead but they are also adding the baby characters like baby mario. They are also talking about adding Rosalina from Mario Galaxy.