Which group of characters debuted as new racers in Mario Kart 8?

The Koopalings debuted as new racers in Mario Kart 8. The group consists of Larry, Roy, Lemmy, Wendy, Iggy, Morton, and Ludwig, who traditionally serve as recurring antagonists in the Super Mario series.

Their inclusion gave Mario Kart 8 a larger villain lineup alongside characters such as Bowser and Bowser Jr. Each Koopaling has a distinct appearance and personality, but they share the same turtle-like species and are associated with Bowser in the broader Mario universe.

Mario Kart 8 was released for Wii U in 2014. Its roster also included several other new characters, including Baby Rosalina and Pink Gold Peach, while downloadable content later added figures such as Link, Villager, and Isabelle.

The question refers specifically to racers new to Mario Kart 8, not characters making their overall Mario-series debut. That distinction matters: the Koopalings had appeared in numerous earlier games, but Mario Kart 8 was their first appearance as playable racers in the kart-racing series.