Extra Points:

In one player mode defeat your opponent and press L to taunt your opponenet just before he dies. Get your character to be in a taunt when the camera goes to check out the scores and you'll get 100 xtra points.

Alternate Costumes:

Go to the character selection screen and enter: c-left, c-right, c-up, or c-down

Play as Captain Falcon:

You must finish the game in under twenty minutes and then beat Captain Falcon.

Music Test Option:

First finish "Bonus Games 1 & 2" with all the characters, even the secret ones(try doing it during practice). Then go to the data screen to select the music test option.

Alternate Character View:

At the character biography screen while holding z, move the analog stick.

Classic Mushroom Kingdom Stage:

First, under normal difficulty(3 lives) complete the game with all 8 original characters. The CMK stage will now be available under versus mode.

Item Switch:

After playing the game more than 50 times in versus mode, the item switch option is unlocked.