Mr. EAD, one of many unlockable racers, has a Mario-like face and a Starman for a belt buckle. His name refers to Nintendo EAD, the development studio that brought us F-Zero X. He drives the "Great Star"perhaps a reference to Mario's fame?
The first course in the Joker Cup is named "Rainbow Road," after the colorful Rainbow Road courses in the Mario Kart series. F-Zero X's Rainbow Road has the exact same shape of Mario Kart 64's Rainbow Road.