Resembling a marlin with limbs, he can be seen at every Marlins home game. He competes in a waterboat race, which is a computer-animated video shown on the screen, during each game. The name, picked by original team owner Wayne Huizenga, is derived from the fact that a marlin is a Billfish, and Huizenga wanted a name that was different from the baseball type names of other mascots (like Slider and Sluggerrr) and one that children could remember more easily. On Mothers Day and Father's Day, Billy is joined by his parents, Bill Sr. and Betty the Marlin. Billy is also seen at games dancing with kids on the field in between innings and making special appearances in the Fan Zone.