The plumber star of the series. His kart is average across the board. When Mario is controlled by the computer, his main item used is the Star.
Similar to his brother, Mario, his kart also have average status across the board. Also like Mario, when computer-controlled, his main item is the Star.
Princess of the Mushroom Kingdom. She has the fastest of all the karts available; however, due to the speed, her kart lacks the ability to turn efficiently. When computer-controlled, she'll usually try throwing mushrooms to make you shrink.
Below par speed-wise. His kart turns the best, but often loses control when hit by larger opponents. Like Princess Peach, he'll try throwing mushrooms in your way when he's controlled by the computer.
Yoshi is the green dinosaur-like creature from Super Mario World. His kart has the highest acceleration. When playing against him, he'll try throwing eggs in your way.
Bowser is the king of the turtle-like creatures called Koopas. His kart is good at crashing into other karts, due to the size. He'll usually try throwing lava balls to stop you.
Donkey Kong Jr.
The son of the famous gorilla, Donkey Kong. His kart's attributes are similar to Bowser's. His main item is bananas, which is what the computer uses when controlling him.
Member of the turtle clan that follows Bowser. Koopa's kart is easy to control, and can squeeze in between other karts. However due to his size, he gets knock away when crashed into by other karts. The item he uses most when controlled by the computer is a Koopa shell.