Fight over 200 multi-player matches.

Beat Adventure Mode or Classic Mode with any character. JigglyPuff will challenge you at the end of the credits, beat her, and she's yours.

Beat the game in All-Star mode.

The easiest way to get Pichu is to clear Event 37, or you could also play 200 VS. matches.

Fight over 100 multi-player matches.

To fight this flab monster beat kirbys reinforcements (kirby team) in 35 seconds or less.

Beat Season 12 5 times and then go on to V.S mode 15 times! Then go to the character selection screen. Then next to Ness you'll see a face similiar to Ness's face and that's Jack.

Play 100 versus rounds (easy way: set it to 1 life and fall of the edge every time)

Beat the game as Mr. Game & Watch in classic mode without losing a life.

Beat Adventure Mode with all 24 characters.

Play the first level of Adventure Mode and get a "2" in the second's place. Next, a cutscene will appear of Mario jumping, and Luigi jumping on him, pummeling him off the castle, leaving you to fight him, and Peach. Beat Adventure Mode, and he will challenge you again. Beat him, and he's earned.

Insert a memory card with a saved game from Pikmin. Begin the game and a Pikmin trophy will be available.

Beat Event 51.

Have a combined total time of 20 hours, or you can play 700 Vs. matches.

Beat Event 29 and Ganondorf will again challenge you. Beat him, and he's earned.

Unlock all bonus fighters to unlock the single player All-Star mode. This mode allows you to fight all game characters, but with less health items.

Beat the game in Break The Targets mode with all fighters.

Beat the 100 man spar.

Earn the Birdo and Pidgit trophies.

Hold L or R and select a stage in multi-player mode. Keep the button held until the match begins. Note: Only certain stages have new music.

Beat the game in 15 Minute Spar mode.

Beat Classic Mode with 10 characters. Young Link will challenge you after you are done. He will be playable if you beat him.

Beat Classic Mode with Mario or play Adventure Mode without losing a life, you can even play on Very Easy mode. Dr. Mario will challenge you at the end of the credits, beat him, and he's earned.

At the home run contest chose Roy. At the beginning hit sandbag with your smash-up attack. Repeat 2 more times. After the third hit make sure that sandbags H.P. is at %55. While he's in the air charge up your B attack and if you did everything correct, you'll hit it over 1300 ft. getting Yoshi's island.

Fight over 50 multi-player matches.

After earning Marth, beat Adventure Mode (Use Marth.) Roy will challenge you after you are finished, beat him, and he's playable.

Hit over 400m in Home-Run Contest mode as Yoshi.

Fight over 150 multi-player matches.

To get Marth, you only need to play V.S. mode once with all origional characters (having one life and dieing does count). After playing with all characters, Marth challenges you. Or... Clear 70 VS. Matches. Marth will challenge you after you are finished. Beat him, and he's playable.