Double Dash!!

The Double Dash!! (or just Double Dash without the exclamation marks) is a move that can be performed only in the co-op play mode of Mario Kart: Double Dash!!. Both players must press at the same when Lakitu's light turns green to perform this move which will make the kart be launched at a higher speed than a normal Rocket Start.

Trivia

 * The name of the move is also present in the title of the game it appears in.