One of the most fun racing games ever made. There's an incredible amount of content and it's extremely replayable and fun with friends. The only thing that kills it is some of the unlocks are very tedious and grindy, or are just straight up obnoxious. It's a blast with friends though and clears every game in the Mario Kart franchise.
Blessed Kirby Air Ride; how on Earth did you get made? One of the more unique and interesting titles in a franchise full of unique and interesting titles. I grew up playing this, and one may even argue it was my first roleplaying-within-a-video-game experience via City Trial's Free Run. Young me walked so modern me could collaboratively write JRPGs inside of MMOs.