Finish the game on the hard difficulty setting. Start a new game, and the super hard difficulty setting can now been selected.
Fat Wario
First go up to the monkey that throws berries. Go in front of the monkey and stand there untill it throws a berrie at you then you can become Fat Wario a when you jump the whole ground shakes.
How To Beat Golden Diva
To beat Golden Diva you first need 10 tokens for the item shop then choose the Black Dragon and go to that level. After the dragon fires the faces start to fly jump on top of one and pick it up and throw it up into the open thing. After you throw all the faces you will have to throw items at the guut and after he shows his ugly face and slams the floor just hit him with an elbow bash. Then hit the lip and your are done.
Multi Princesses
There are different types of princesses, there are two that I know of. One is where you get all of the treasures. Another is where you miss around two. There may be more, but that's all I got at the moment.
Ruby Boss - Cuckoo Condor - Easier Win
Use a Big Fist from the Item Shop to reduce him to 2 Health Points.
Save Coins
When playing a mini game attempting to win gold coins, and you fail to gain any or only win 1, quickly turn off the console and then back on again and you will be able to re-use your 5000 coins to try again.
The Flower
In Wildflower Fields when you get to the big sunflower pick up a caterpillar and throw it at the center of the flower. The yellow in the center will decrease and you will get 500 coins.
Topaz Boss - Aerodent - Easier Win
Use Large Lips from the Item Shop to reduce his Health Points.
Treasures
Try to beat the bosses as fast as you can, because you want more treasure chests, because its pays off in the end of the video game.
Unlimited Mini Games
When you are playing a mini game and you are about to lose, before it says GAME OVER, shut the gameboy off . Turn the gameboy on and you will still have you money, and you can keep playing until you win!
Wario Karaoke
Enter the sound room and highlight the "Exit" option. Press Select + Start + R + L + Up to unlock Wario Karaoke. Alternately, get gold crowns by collecting over 10,000 coins in all levels to unlock the Wario Karaoke (music test)
option.
Wario Karaoke control
Press Up or Down to change the pitch of the song. Press Left or Right to change the tempo of the song. Press L or R to toggle between a green CD, yellow CD, or just the lyrics.