Things You'll Need
Instructions
Method One: Playing Versus Matches
Play versus matches. Playing normal matches would make this incredibly tedious, so the best plan is to experiment with the match settings to make the matches as short as possible.
Set up a one-on-one stock match with you and a computer-controlled player. Be sure to set the stock to one life per player, start the match and immediately jump off the stage. A lost match still counts as a match, after all.
Unlock characters roughly every 100 matches until you reach 1,000. The character order is as follows:
50 - Jigglypuff
Method Two: Playing Single Player Modes
Complete various goals in the game's single-player modes. Though method one will probably be faster, this method is certainly more fun, but also more difficult.
Complete classic mode using Mario without continuing to unlock Dr. Mario.
Complete the 100 Man Melee and then defeat Falco to unlock Falco.
Complete Event 29 and then defeat Ganondorf to unlock Ganondorf.
Complete Adventure or Classic mode once to unlock Jigglypuff.
In Adventure mode, finish the first stage with a 2 in the seconds meter on the timer and then defeat Luigi to unlock Luigi.
Finish Classic mode with all 14 standard characters or play as every character in Versus mode to unlock Marth.
Play Versus mode (or leave your console on in a Versus match) for 20 hours and then defeat Mewtwo to unlock Mewtwo.
Complete Classic, Adventure or the target test with all characters to unlock Mr. Game &Watch.
Complete Event 37 and defeat Pichu to unlock Pichu.
Complete Classic mode using Marth and defeat Roy to unlock Roy.
Complete classic mode with 10 characters and defeat Young Link to unlock Young Link.
100 - Dr. Mario
200 - Pichu
300 - Falco
400 - Marth
500 - Young Link
600 - Ganondorf
700 - Mewtwo
800 - Luigi
900 - Roy
1,000 - Mr. Game and Watch