Sorry, but there is only ONE right answer, and that's the GOAT racing game Diddy Kong Racing!
Some of you may be getting tired of me using DKR as my answer, but this question is the primary reason why I love DKR so much!
It was cool enough that DKR had an adventure mode to set it apart from any other racing game. But if you put in the code JOINTVENTURE, you could play the adventure mode with a friend (which definitely made it a little easier to beat - especially mirror mode)!
I'm not exaggerating when I say that
@mariomaestro and I have beaten the game together 3-4 times over the years!
I can't recommend this game highly enough! If you like racing games, play this game!
Honourable mention 1: Donkey Kong Country 2: Diddy's Kong Quest. I'm currently playing through the co-op of that with
@mariomaestro. Best 2D platformer outside of the GOAT Super Mario World!
Honourable mention 2: Return of the King. Another game I've played with
@mariomaestro.
Honourable mention 3: Halo series (well the ones made by Bungie anyways).
