Go outside the castle, near the waterfall. Climb the third tree from the waterfall. Do a handstand on top of the tree to get a one-up. Then, enter the castle’s first floor. Now return outside and climb the same tree. Do another handstand for another one-up. Repeat this trick to collect an unlimited amount of lives.
Infinite lives (Japanese version)
During the first fight with Bowser, continuously avoid him and collect all the coins that appear. Continue to do this until 1000 coins have been collected. Then, a green “M” will appear next to the number of lives remaining. From this point on, when a life is lost, the number of lives increases. While gaining lives will actually lower the number of lives remaining. The cheat will end if the number of lives reaches zero, such as when Yoshi gives Mario 100 lives after obtaining 120 stars. This trick cannot be done on the North American version as it only allows 999 coins to be collected. Note: Once the game is ended you will no longer have infinite lives.
Butterflies may appear on courses 2, 12, and 13. Punch the butterflies to turn them into round black bombs that will chase Mario. Then, the bombs will explode or turn into one-up mushrooms.
One-ups in third Bowser battle
Walk behind the top left pillar to collect a 1-Up if you lose a life during the battle.
Obtain all 120 stars and go outside the castle. Climb inside the cannon opening that is now located where the grating was near the Fish Pond. Aim to land Mario onto the roof, where he will meet Yoshi. Then, he will speak to Mario, award a 100 life bonus and a triple-jump move, and quickly leave.
Alternate Bowser message
Obtain all 120 stars and return to the final fight with Bowser to see a different message.
Very big penguin
Obtain all 120 stars and return to Course 4 (Cool, Cool Mountain). Before entering, select the Big Penguin Race. Then begin the game and jump into the chimney of the house at the beginning of the level. Now the penguin will be even larger than before.
Control ending sequence camera
After beating the game, use the Analog-stick on controller two to control the camera in the scene featuring Mario and the Princess. The camera is also controllable on the Credits screen.
Control the speeds of Tick Tock Clock
In order to control the speeds in the Tick Tock Clock, you will need to play close attention to the minute hand. When the hand is on the 3, the platforms in the clock will be slow. Like wise 6 will be medium speed and 9 will be fast and at 12, the clock will have stopped completely.
If you have taken damage just jump in some water that you can be submerged in and rise to the surface then you will have your energy filled up.
Raise Water Levels in Wet Dry World
There is a way to control how high the water level is in Wet Dry World when you enter it. If you jump high into the painting, the water level will start off high. If you jump low into the painting, the water level will start off low. There are several different water levels that it can start as, and these are determined by how high you jump into the painting.