Hey, since ya talking about luigi I saw people posting codes that are fake. Have fun! Go crazy! and create one that may not even be creative!
To play Pac-Man:D
First as Luigi spin around three times before you start the game. Tell your mom to get you a gamboy advance with a Pac-man game. When she buys it play for a while then start the game when you do you'll see dot's appear on the screen that meant Pac_mans in the game. Play file X and your Pac-Man! Don't forget to eat Dots! But that's another code

"Using the Flower Power attack"
After speaking to Yoshi, he jumps off of the roof and into the waterfall, right? You must follow him. Go into the water and go near the far corner of the water fall. Aim the control Stick up and you can start to swim up the waterfall. Its very hard to do because u must beat the current. Get behind the waterfall to find Yoshi. He will be surprised to see u and will reward you with a 'Fire Cap'. Once equipped, Mario can shoot fireballs by pressing Z + B.

So was this a good enough secret?

To get invisable Cap.
First put your control stick up before you turn on the game. Keep pressing the buttons to make you controler go back to it's original position. Go and get every single cap corse again 64,000,000,000,000 times. When your done Peach will escape and give you the invisable cap. Bowser will be right in front of you and can't see you so you can destroy him there! With this cap your equiped with things you never saw!
Toad going to the bathroom.
The Boos making fun of each other.
Luigi creeping behind you.
Peach keeps escaping.
Bowser sleeping waiting for Mario.

to make mario do a quadrupal jump hold the controls stick left press the l,r and start 5 times spin around u will fall though the floor and appear in the castle where bowser will be kissing peach and bowser will say "do u mind? ill give u sumthing if u go away and then u can do the quadruple jump! lol this is fun making things up

See Daisy. As Mario eat too much candy and Mario should turn green. Go to Princess Daisy slide and ride down without throwing up. You should see Princess Daisy by the star and she will help you through your game!

see neopets

run around the big boo 100 without getting hit and butt slam him and then a wierd yellowish hat will come put it on and walk though the statue in the middle u will fall in the castle where a bunch of neopets will be waiting for you to feed them!

Those are all great Fake Codes everyone! Good idea for a thread, Melody! Here is one I made up:

Name: How to Play as Princess Peach.
Description: First, fight Bowser the last time, then when you see the key, grab it. When it shows Princess Peach's cake that she made for Mario, press these buttons in this order: B, A, C-UP, C-Right, C-Left, C-Down, Z and R. If you did it right, you should hear Peach say, "It's-A-Me, Peachy!" Then Reset the game and the file that you did it on will have been erased, but instead of Mario's face on the file, Princess Peach's face is there. When you enter the file with Peach's face, you will be Princess Peach instead of Mario and you have to save Mario from Bowser. Peach has her regular voice, and all of her own moves and attacks!

lol play as bowser:

as peach go on the last fight grab bowser throw him into the bombs 3 times on the last ending [with the cake press c up c down left right [on the d pad] l,r [shoulder buttons] and z bowser will say its me bowser

NOTE: if you haven't got all the stars as peach bowser will say bwahahahaha you are not worthy of playing as me! and will erase all files and you won't have peach! and another thing on other versions [mainly the adult ones][made up] he will say now you can play as me the fat annoying fiery git!
I luuuuuv making these up

Good one, shadows power! Here is another one:

Name: How to Play as Yoshi and the Bunny.

Description: First go on the top of the roof. When you see the Lifes, DO NOT get them, just talk to Yoshi. When Yoshi jumps into the Water Fall, turn off the system without saving your game. Then turn the system back on and go to same file when you did the above. When you enter the file, shoot up on the roof again. When you get on the roof, Yoshi will be gone and a note will be in his place. Press the 'B' button by it and it will get bigger so you can read it, it will say: "Dear Mario, This is Yoshi and I had to deliver the Lifes on this rooftop to Toad, I will be back soon. Yoshi." After you read it, go into the Basement and the Bunny will be back, talk to him and he will say that he saw Bowser grab Yoshi, he will then say to follow him. Follow the Bunny until he leads you into Bowser's Secret Chamber, then you will see Yoshi tied up and the Bunny will untie him and talk to him. Yoshi and the Bunny will walk over to Mario and say, "Thank You for helping us, we will now help you!" Then a message will pop up that says, "Do you want to Save?" Press 'Yes' and then Reset the system. When you turn it on, the file that you played it on will now have Yoshi's, Mario's and the Bunny's face. Play that File and your game will be erased and Mario can ride on Yoshi, the Bunny can ride on Yoshi, Yoshi will have no one ride on him, you can play as the Bunny or you can just play as Mario with Yoshi and the Bunny following you, press 'L' to switch between characters!!!

cool fake codes everyone

name: how to play as big boo
discription: you beat the game as the bunny and head for bowser if you have all the stars you will see big boo and he will say "bowser is not here so you have to fight me so get ready to be eliminated" then he will grow ten times bigger than bowser and he warps you to the ghost level you have to get all the stars again then he warps you and himself to a huge platform high above a flaming pit! then the big boo says "say goodbye, bunny!" and this ghost is not shy it will rain bob-ombs you have to pick them up and throw them at the big boo he will vanish after a few hits and say "you may have one the battle but the war is not over yet!" the platform will start going up once it reaches the top you should see a ledge and the platform will tip over you have to long jump over there if you make it a gaint star that is the size of bowser will appear grab it the rabbit will get a cape and fly to the forest it shows the cast list and instead of seeing a cake you will see a big carrot while you are looking at the carrot press A A B Z L R Z C-left and START if you do it right you will hear big boo laugh and lakitu will come on the screen and say "do you wish to save?" pick yes and reset and big boo will appear on the press start screen

This message was edited by B T Master1 on Jul 12 2002.

play as sonic the hedgehog [i wish]

as big boo get all the stars which is simple beat all the bowsers which is hard and at the end fly upwards instead of getting the big star and there will be a blue platform butt stomp it and sonic will chaos control in nd talk to him he will say follow me! he will run around the star 10 times and u have to follow him EXACTLY or else he will chaos control away collect the star and u can play as him!

Here is another:

Name: How to fight Bowser a 4th time and get a diffrent ending.
Description: As Luigi, go to the level called, "Lethal Lava Land" and select Star five. As soon as you get into the Level, press 'START.' If you did right, you should hear Bowser laugh and then see him in front of Mario. Follow Bowser without getting too close for him to see you and too far away for you to lose him. Suddenly he should stop and there will be Movie Clip of Mario running into Bowser and Bowser falling down into a hole he stopped by, then Mario will turn around and start running when he gets sucked up in the hole. Mario will then be on a Arena with Bowser and Bowser will say, "You foolish plumber! I will now kill you and put you out of your misey of missing Princess Peach!" Then he will try to push you off the edge of the platform and you have to press 'A' repeatedly to knock him off. If you win, there will be a diffrent ending where Peach throws a Party for Mario as a 'Thank You' and Luigi, Yoshi, the Bunny, Pacman, Sonic and Toad will all be there along with Princess Daisy, It is a 1 Hour Movie Clip!

How to play as toad

When you gain acess to the nbasement, talk to the toad that you first meet and while he's talking, hold L,R,Top-c. He won't be talking anymore so you then press A,Up on the stick and pad, and Z. A cap block will appear and toad will ask you to fight him. Beat him and you'll be able to play as him.

Get Peach

To get Peach, first get every star, then beat Bowser, then when peach is kissing mario, press the A button. After you get to the end picture with the cake, hit reset and go into the castle. Peach will be standing on the sun pic and ask mario to walk with her.

name: find 50 secret levels + 50 new bosses
discription: as toad go to big boos haunt select star 6 "eye to eye in the secret room" after you get all the stars in the game grab the vanishing cap go find the huge mr. I beat him and instead of a star you get flowers a hole in the wall will appear and a snowed on tree and a palm tree a stone platform will appear as well there all teleports pick the right one you get warped to a secret level the wrong one puts you in the flaming pit with the huge platform over it