That's the Mega Mushroom from Mario Kart Wii at work here.
"Where we at, where we at??" 😄
Just like in Double Dash, they're exclusive to their respective drivers. (I would always choose Toad and Bowser Jr. for that reason.)
For sure I recognize the B-Dasher from Mario Kart DS.
Fly your way to the finish line.
Just needed to have that emphasized.