Press Select while playing a normal game to change into different Marios or Luigis (Mushroom, Fire Flower, Super Leaf, Frog, Tannokie, and Hammer Brother).
Getting the boot
Hold Y and press Select.
28 P-Wings
Complete the game, then press Start at the ending screen. The next game will begin with 28 P-Wings per brother.
Random world
Wait until Mario and Luigi begin running around during the opening sequence. Press random buttons on the controller. The game will begin at a random world after the number of players are selected.
Whistle Room
Go to world 1-3. Towards the end of the level, there should be a white rectangle floating in midair. Jump on it, then squat down. In a few seconds, you should fall through. Go to the end of the level. In a few seconds, you should see either Mario or Luigi { whichever Mario Brother you are } on a platform on the left side, and a Mushroom Person on the right. In the middle of the screen, there should be a box. Run to the box, and press B. A whistle should pop out. To use the whistle, you should be on the level select screen. Press B, and there at the bottom of the screen in a pink strip should be a whistle. Scroll over to it and press A. It will take you to a Warp Zone. Choose a world and press A. You can use your whistle in that game only.
Double Warp
Receive two whistles and use one to get to the warp room. In the warp room use the second whistle which will take you to the last part of the warp room. This will get you to level 8 to defeat king Koopa.
Desert World Whistle
Towards the end of the Desert World you can obtain another whistle. In the top right corner in the far right hand corner of the world there is a rock directly next to the path. Use the hammer you obtained from one of the Koopa Battles to break it. Once you've found it though you must defeat two fireball spitting Koopas to get it make sure you at least have a mushroom before going into this battle just to be safe.
Warp Whistle II
In world 2, after you beat Level 4, there is a stone right beside 4.Use the hammer and then there is a path that opens up.Fight the fire brothers and after you do that in the box is the Second Whistle.
Game Genie Codes
All codes (except as noted) work for Luigi as well as Mario.
SLXPLOVS Infinite lives for Mario and Luigi
AEKPTZGA 1 life for Mario and Luigi after continue
AEKPTZGE 9 lives for Mario and Luigi after continue
ELKZYVEK Power Jumps
EZKZYVEK Super Power Jumps
EAKZYVEK Mega Power Jumps
GZUXNGEI Multi-Jumps
With the next code, if you let MArio or Luigi drop too long, you can't sky walk until you touch the ground again
SXEZSKOZ Skywalker
OXKZELSX Super speed running
XVUXNUEE Turbocharged running
You must be Raccoon Mario for the next code to work
AANZKLLA Can raise power meter while standing still so that you can fly from a standing start
PEUZUGAA Start on World 2
ZEUZUGAA Start on World 3
LEUZUGAA Start on World 4
GEUZUGAA Start on World 5
IEUZUGAA Start on World 6
TEUZUGAA Start on World 7
YEUZUGAA Start on World 8
YPXXLVGE Mario (not Luigi) can re-use items again and again
SZUEXNSO Restore powers after playing an action scene (e.g. if you were "Fire Mario" on the map screen, then entered an action scene, died or changed to "Frog Mario,"you would return to the map scene as "Fire Mario")
ZEUXKGAA Start the game as Fire Mario
LEUXKGAA Start the game as Raccoon Mario
GEUXKGAA Start the game as Frog Mario
IEUXKGAA Start the game as Tanooki Mario
TEUXKGAA Start the game as 'Sledgehammer' Mario!
If you use any of the next five codes to defeat Bowser, stand in front of the door and hold "Up". as soon as the door opens, you will pass through into the chamber where the Princess is held. If you don't do this, you may get caught in Bowser's time trap and the game will pause forever!
XUKXGLIE Start and stay as Super Mario
UXKXGLIA Start and stay as Fire Mario
NXKXGLIE Start and stay as Raccoon Mario
OUKXGLIE Start and stay as Frog Mario
XNKXGLIE Start and stay as Sledgehammer Mario
SZKIKXSE Invincibility after changing up from Super Mario (e.g. to Raccoon, Frog, etc.)With all of the following codes, you will find that you change into Super Mario if you die again:
AEOSSZPA + PAOZTGAA Change to Super Mario if you fall off screen and die
AEOSSZPA + ZAOZTGAA Change to Fire Mario if you fall off screen and die
AEOSSZPA + LAOZTGAA Change to Raccoon Mario if you fall off screen and die
AEOSSZPA + GAOZTGAA Change to Frog Mario if you fall off screen and die
AEOSSZPA + IAOZTGAA Change to Tanooki Mario if you fall off screen and die
AEOSSZPA + TAOZTGAA Change to Sledgehammer Mario if you fall off screen and die
Hammer Suit
The hammer suit will make you invunderable to fire and you can kill ghosts with your hammers.