Old Super Mario:
     This  opens up a bonus level just above the 'random' stage select
in multi-player mode (complete with the old SMB soundtrack too!). Have
player  one  be  Mario,  and player two be DK. Fight eachother in DK's
jungle  stage.  Have  DK  win. This should open up the new stage. Also
reported  as  you have to beat the game with every character including
the secret ones

Extra Points:
     The way to get extra points is to first get to the boss..then (if
you  can)  beat  him  within  1:00  minit  and  you  should get 40,000
points.......

Easy Pokemon win:
     First  start  a battle with someone. Find a pokeball and throw it
below  you.  Quickly  push R so you can grab the opponent but hold it.
Pokemon   will  come  out.  Hopefully  it  will  be  Meowth,  koffing,
charizard,  or  blastiose.  If  its  one of these your in luck because
while  your  holding  your  opponent the pokemon will be attacking the
enemy, but the enemy can't do anything.

Samus without Her Armor:
     First  unlock  Ness,  then select versus mode and choose Samus as
your  opponent.  This  trick  is  easier  if  Samus  is set as a human
controlled   player,   so   she   stands   still.   Next,  go  to  any
place(preferably the ship) and fire the PK thunder at yourself so Ness
slides  into  Samus.  Then  right as Ness hits her, pause the game. If
done correctly Samus will no longer be wearing her suit.

Evil Ness:
     Beat  the  game  on "Very Hard" with Ness with only one life, and
ness's face on the character select screen should become dark and have
devious eyes(This might work with other characters).

Evil Link:
     Beat  the "Very Hard" level with only 1 life and Link will become
evil looking. Pointed eyebrows and a sinister look.

Kirby's Power Loss:
     Everybody  knows that Kirby can swallow his opponents and take on
some  of their powers in this game, but what if you accidentally "ate"
a  character  you  didn't want -- and you want to pursue someone else?
Simple:  Just press the L Button to pull of Kirby's "Hello!" taunt and
he will discard whatever power he took on.

Play as Jigglypuff (Purin):
     Beat  the game with any character on any difficulty and number of
lives. Then beat Jigglypuff.

Play as Captain Falcon:
     Beat the game in 20 minutes. Then beat Captain Falcon.

Play as Ness from Earthbound:
     Beat  the  game  on  normal difficulty and with three lives. Then
beat Ness.

Play as Luigi:
     Complete  Break The Target with the eight original characters and
one bonus character. Then beat Luigi.

Sound test:
     Complete  Bonus  Games 1 and 2 with all characters, including the
secret ones.

Alternate costumes:
At the character selection screen, press C-Left, C-Right, C-Up, or C-Down. 

Change Outfits:
     You  can  change  your  characters' outfits by tapping the four C
Buttons at the character select screen.

Mew in Pokeballs:
     Unlock all four bonus characters.

Item menu (VS mode):
     Play VS mode 50 times.

Classic Mushroom stage (VS mode):
     Beat the game with all the original characters.

Get Raichu:
     To get Raichu (the evolved form of Pikachu), beat the game on all
skill  levels  with  one  life  in  your  stock, after that, go to the
character select screen and press up and start after you have selected
him.  Also,  if  you turn off your system and do not have an expansion
pack,  you  must redo the trick. If you do have an expansion pack, the
game will not delete him.

Brutal Death:
The following must be used to do this:
1. A pokeball (will work with Charizard, Maybe others)
2. A green shell
3. Link's stage's Tornado
4. Two player works best

     Place  the  green shell near a place where a tornado will appear.
Pick  up  a  pokeball.When  your  opponet  comes up,throw the pokeball
behind  the  green shell.If it's charizard,it'll hurt your opponet and
send  the  green  shell into your friend.If a tornado appears and your
friend  gets  caught  while  being  hurt,  It'll  throw him out of the
stadium.

Bonus Practice #1, Break The Targets:
     When  playing  as  Yoshi, to get the target on the far right, use
the  Mega  Headbutt (Left or Right + A) next to the side of the target
hill.

Bonus Practice #2, Board The Platforms:
     Use  the  following  strategy when playing as Jigglypuff/Purin on
the  last platform. Since Jigglypuff does not have an extra jump (Up +
B),  run  and  jump  from  the  edge  then  press B. Repeat this until
reaching  the platform. Pace your jumps so he can go farther. Practice
this on the "walk on water platform".

Borrow a life:
     Begin  a  team  game under versus mode. Press Start if you lose a
life  to take a life from your partner, if he or she has more than one
remaining. Alternatively, press A + B + Z + Start.

Control credits screen:
     Press  one  of  the  following  buttons during the credits. Press
Analog-stick  to change the angle and move the target. Press Start + A
to scroll faster, or to return to normal speed. Select a name with the
target and press A to view details about their work in the game. Press
B to pause or resume the scrolling.

Self-destruct:
     Hold Z or R (block) until your character explodes.

F-Zero X track:
     If  you  get  a  total  score  of more than 1 200 000 you get the
special  F-Zero X race track. Were you can fight and dodge the cars at
the same time.

Suicide kill:
     Donkey  Kong  has  the ability to pick up barrels and walk around
with them for a short time, well, he can do the same with players, get
near  the  edge  as  DK, and press grab once, if you press it too many
times  you  will  pick up the character and throw him immediately, you
don't want this, wait a second and move to the left and right until DK
places  the  character  on his back, once DK has the enemy on his back
run  and  jump  off  the edge immediately, if done correctly, you, and
your  enemy  will  not  be  able to get back up before DK is forced to
throw the enemy, you will have successfully sealed both of your fates.
If  you  really know what your doing, you might be able to jump at the
last moment just enough to make your enemy go down first, you thus win
the  match if he was on his last life. Kirby can do something similar,
his  main  grab  shoots  up and then down, if you can get this move to
land  over  the  edge,  your enemy will be under you, if he was on his
last  life,  he  should  die  first.  Yoshi's suicide is very hard, it
almost requires chance, you have to get hit hard enough to knock Yoshi
off the edge without making him lose whoever is in his mouth, you both
fall.

Giant Mario:
     When  playing  as  Mario,  press  L and he will grow bigger. (You
can't move when big though.)

Hint:
     You have to have the Classic Mushroom Kingdom in Vs. mode and the
Item Switch. Then go to the Item Switch and turn everything off except
the  bumper. Then go to Vs. Mode and pick the character Fox (I suggest
you  make the Comp. a level 1, then he won't mess you up). Then select
the  Classic  Mushroom  Kingdom.  Wait for a bumper to appear and then
grab  it.  Bring  it over to the tunnel nearest to the top and stand a
little ways from the tunnel or it won't work. Throw it up and then use
your  Deflector  (Down  B).  Let  it  bounce back and forth until your
deflector  breaks.  If  you stood far enough away it should be hitting
you  and  you  should  see  a giant "Hitt" symbol and your health will
increase  rapidly. If you are not at 999% do it once more. This is fun
for sudden death matches.

Travel in tubes:
     On  the  Mushroom  Classic  Stage,  go on top of a tube and press
down,  and  you  will  go  down the tube into a different tube.A great
excape  route  from attacks.(Note: you can come out of the tube in the
pit so press jump to get out of it.)

Item Switch options:
     Play  versus  mode at least 50 times. This unlocks an item switch
option that you take control over. Things like items and the number of
times it can appear will be controllable.

Unlock Waluigi:
     If you manage to get a score of 1.000.000.000 you unlock Waluigi.

Make Capt. Falcoln Fart:
     To make Capt. Falcon fart, go to training mode and choose him and
choose Link's stage. Make sure that you have your opponet next to you.
While jumping, press Down + A as you land.

Evil characters:
     With  anyone  you  can make them evil by beating the game on hard
with  one  live  using  no continues. You can make Pikachu's eyes turn
onto the side of his head.

Getting the mushroom kingdom arena:
     Beat  the  game with all characters then play in every arena (you
can use any settings you want)

Pikachu's easy thrasher:
     If  you  play  Vs.  Mode  with only 1 human player and 1 Computer
Players(maybe  3  if your good enough or 1P Mode choose Pikachu as you
then  play  at  any  level  (Dream  Land  would  be a good choice)with
computer  players  at  about  level  4 to level 9. Then as soon as the
match  starts  or when the opponent is asleep or can't move then go up
really  close  to  your enemy and start headbutting him by pressing A.
Keep pressing A until your enemy uses his sheild then tap A as fast as
you  can.  After  a  while he will have a lot of damage and his shield
will  be  tiny.  Then  if  it  gets  to  small  it will break! If it's
Jigglypuff  she  will  die  but  other players will go unconscious and
start  groaning. Then as quick as you can press A tap right and you'll
thrash the Computer players.

More Points on 1P mode:
     Only  throw  your opponenent and do nothing else and you will get
Judo  Warrior  on  special bonus which gives you 5000 points and throw
down which gives you 2000 points!

Rich with points with using a single attack!:
     On  1P  mode  on  Pikachu's stage and fight jump over Pikachu and
land on the building with a H on the top then keep on jumping to where
Pikachu  was  on at the start to the building with the H. Then Pikachu
should  copy you then use quick attack if it falls between the gap and
it  should  miss  the H building then it will be paralyzed and die. If
you  didn't  do damage to it you'll be awarded 60,000 points.(WARNING!
When  doing this don't fall off yourself and use B up and do damage to
Pikachu  if  you  are  Pikachu you must be extra careful.) On Giant DK
stage just stand still but if your Allies are in trouble help them out
and  if  you  don't  do  to much damage you'll get DK Defender and get
10,000 points instead of 60,000.

Kirby's killer thriller for boss:
     If  the  boss  uses an attack press B down just before he uses it
and  you  won't get any damage! Then press B up when he's finished the
attack and when he's still hurt him then when he does an attack repeat
what you just did.

Yoshi's Killer thriller for boss:
     Jump  in  the  air  and hold A down while in the air. If you were
high enough the boss will get about 65 damage. Not too shabby.

Points:
     On 1P mode on a normal round complete it within 30 seconds to get
10,000 points. Also if you press L just before your enemy dies you get
100 points.

Home Run:
     Get a bat and when your next to somebody press A tap and you glow
and  when  you  hit  someone  it  will make a loud screaming sound and
they'll  only get about 8 damage but there bound to die. Also Ness has
a fake bat so when you press A tap with out a weapon it will scream he
does 20 damage but it's unlikely that he'll die. Also A tap works with
other weapons but it does not scream and does not send them flying.

----------------------------------------------------------------------

Japanese version 

Play as Jigglypuff (Purin):
     Beatthe  game with Captain Falcon on any difficulty and number of
lives. Then beat Jigglypuff.

Play as Captain Falcon:
     Beat  the game with any character on any difficulty and number of
lives. Then beat Captain Falcon.

Custom menu:
Play Yoshi VS. Kirby 100 times for multiplayer options. 

Item menu (VS Mode):
     Get 100 kills with any characters.

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Pokemon in the Pokeballs:

The Pokemon in the Pokeballs have the following powers. 

Beedrill:
     Flies off to get the rest of its hive to attack the opponent.

Blastoise:
     Blasts opponent with water spray.

Chansey:
     Pops  out  and  give you an item. In a second appearance, it just
throws Chansey eggs.

Charizard:
     Starts to breath fire in each direction.

Clefable:
     Arrives and mimics one of the other available Pokemon's attacks.

Goldeen:
     Flops around trying to hurt opponent.

Hitmonlee:
     Comes out and flies at the opponent doing a kick attack.

Koffing:
     Arrives and starts blasting foul smoke in the air.

Meowth:
     Pops out and showers out coins that hurt opponent.

Mew:
     The  special  secret  151st  Pokemon  makes his appearance... and
flies away.

Onix:
     Shows up, flies up top, and then boulders drop from the ceiling.

Snorlax:
     Pops out, flies up, and then comes down huge, hurting your opponent.

Starmie:
     Finds opponent and blasts them with rays.

Charmander:
     Just blows fire in one direction (only in Silph Co. stage).

Venusaur:
     Razor  Leaf  attack;  leaves  from  this Pokemon fly at opponents
(only in Silph Co. stage).

Porygon:
     Rams you or the opponent (only in Silph Co. stage).

----------------------------------------------------------------------

Keeping your opponent off the platforms:

     Use  the  following moves when playing as the indicated character
to knock your opponent off the platforms.

Mario and Luigi:
     Press B to throw a fireball when they try to come back.

Ness:
     Press  B  for the PK Fire if they come near your character in the
air. Your opponent will be pulled down and paralyzed once it hits.

Yoshi:
     If  you  are near the end of the platform, wait for your opponent
to  approach. Then, press B to turn them into an egg. If you are close
enough  to  the edge, the egg will make them fall and they will not be
able to get back up.

Donkey Kong:
     After  knocking  an opponent off, press B to charge up the punch.
Use the punch when they are close enough while in the air.

Kirby:
     Press Up + B near the edge when your opponent approaches.

Link:
     Press  B  to  throw  the  boomerang  after  knocking them off the
platform and they try to get close again.

Fox:
     Press B to keep firing the blaster.

Samus:
     Press  B  to  charge up the gun, then shoot it when a knocked off
opponent returns.

Pikachu:
     Jump  and  press  B  to shoot a little ball of electricity. If it
hits a returning opponent, they will be paralyzed.

Captain Falcon:
     Press B to use the Falcon Punch when your opponent tries to return.

Jigglypuff:
     Press  B  to  use  the lunging punch when a returning opponent is
close enough.