From the Super Mario Wiki
Donkey Kong uses the Slide-Attack against Bowser's Koopa King

The Slide-Attack is an attack that can be performed in Mario Kart: Double Dash!!. This move can only be used in co-op mode, and it has the ability to spin out opposing racers and steal their items. To use the move, the player that utilizes the items must either press the L Button button to do a Slide-Attack to the left, or the R Button button to do it to the right. Because the move quickly shifts the kart slightly to the left or right, it can either be useful or a hindrance to the driver, depending on the time used.