Power Hit: (A + Smash Forward)
Every character has the ability to make stronger attacks. By smashing the control stick forward while pressing the A button, your character will do a considerably stronger attack. You can also hold this move, and charge it up for an even more powerful move.

Don't Give Up: (B + Up)
Almost all characters can do an additional jump move by pressing B and up. When you get knocked off the edge of an arena, do a midair jump, and then follow it up with this extra jump. It's surprising how many times you can save yourself from falling by using this maneuver.

Throwing Items: (Z + direction)
Some items use ammo, and once you're out, the weapon is useless. However, they make excellent projectiles. When your SuperScope or Ray Gun don't have any shots left, use the Z button with a direction to throw the weapon at your opponents.

Evasive Roll : (R + Forward)
This is a very effective strategy for turning the table on your opponents. While facing an attacking player, hit R and forward, and your character will perform a roll, and get behind your attacker. This presents and excellent opportunity to smash your opponent in the back.

Evasive Dodge : (R + Down)
If you know that you're on a colision course with an attacking player or flying object, you can sidestep the attack. When you press R and down, your character will drop a bit, and flash. This allows objects to pass right by you, without you getting hit.