Eagleland: Fourside
Play 100 VS matches.
Submitted by GR0UD0N. 100% success rate. 

Young Link
Beat Classic Mode with 10 characters. Young Link will challenge you after you are done. He will be playable if you beat him.
Submitted by GR0UD0N. 

Pichu
The easiest way to get Pichu is to clear Event 37, or you could also play 200 vs matches.
Submitted by GR0UD0N. 

Mewtwo
Have a combined total time of 20 hours, or you can play 700 vs matches.
Submitted by GR0UD0N. 

Ganondorf
Beat Event 29 and Ganondorf will again challenge you. Beat him, and he's earned.
Submitted by GR0UD0N. 

Dr. Mario
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.
Submitted by GR0UD0N. 

Jigglypuff
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.
Submitted by GR0UD0N. 

Mr. Game & Watch
Beat Adventure Mode with all 24 characters.
Submitted by GR0UD0N. 0% success rate. 

Luigi
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.
Submitted by GR0UD0N. 0% success rate. 

Roy & Marth

• Marth
  To get Marth, you only need to play V.S. mode once with all original 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.
• Roy
  After earning Marth, beat Adventure Mode (Use Marth.) Roy will challenge you after you are finished, beat him, and he's playable.

Unlock Poke Floats
Play 200 VS matches.
Submitted by GR0UD0N. 

Mushroom Kingdom 2
Get Birdo or Pidgit trophy from Super Mario Bros 2.
Submitted by GR0UD0N. 

Superflat World: Flat Zone
Unlock Mr. Game and Watch and defeat Classic mode with him.
Submitted by GR0UD0N. 

Final Destination
Clear all 51 Event Matches.
Submitted by GR0UD0N. 

Dreamland, Kongo Jungle and Yoshi

• Dream Land
  Beat Target Test with all 25 characters.
• Yoshi's Island
  Hit at least 1,323 feet in the Homerun Contest with Yoshi. To do this, first grab the Home-Run Bat. Then keep doing Yoshi's Down + A until the time is 3 seconds. Finally, hit it with the bat and if you do it right, you will hear a sound like Articuno's Blizzard on Super Smash Bros Melee.
• Kongo Jungle
  Finish 15-minute Melee with any character.

Bonus Mario Stage
Complete classic mode with Princess Peach on any difficulty setting without losing a life to unlock a classic stage from Super Mario Bros 2.
Submitted by GR0UD0N. 

A Trick for Getting Mewtwo Easily
You need 2 controllers and it must be nighttime. Go to VS Mode. Go to the V.S.Mode Settings and set the Melee time to 99:00. Pick to have 2 HMN (Human) controlled characters (I recommend Pikachu for P1 Since he is great for fighting Mewtwo). Fight at Pokemon Stadium. Put your characters on the pokeball and leave it on overnight. When you wake up, do another VS Mode Melee Battle and pick the character you are best with. Win and battle Mewtwo.
Submitted by GR0UD0N. 0% success rate. 

Shiek May Never Fall
While playing as Shiek, if you are about to fall, quickly transform into Zelda (B + Down) and use Farore's Wind (B + Up) to return to the stage.
Submitted by GR0UD0N. 

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