Super Smash Bros. Melee/Dr. Mario

Doc’s Up- Cancel
Doctor Mario can actually cancel his Up-. After you press Up (Up and to the Right preferably), to cancel it, quickly tap in the opposite control stick direction. If you succeed it will be very noticeable, just keep practicing because this is one of those things that will take time to master.

The initial control stick direction is BARELY above where it would be for the cape. Then you have 4 frames to move straight across the analog. Much easier to do against a target because of the hitlag. Try in slow motion in practice mode until you get the movements down.