First, do the Stuck flying in the middle of nowhere glitch and do it so that you end up in the first level. You'll still have the weird Huffin Puffins with you - make sure you bring them along and conserve them. Now, jump under any message block and a blank message will open up briefly. Now, throw a Huffin Puffin at the message block so that it hits it more than once. The screen will glitch up, in different ways, depending on your game. For most, the text box will remain on the screen.
For my game (and possibly others'), many of the sprites became invisible (you weren't able to see Yoshi, ? clouds, or enemies. Also, the different layers of the image got switched (some background images may become parts of the foreground). You could no longer enter pipes, make eggs (it acted as if all enemies were the non-egg-producign type when swallowed), and you could not shoot ? clouds. You could, however, see and collect coins. If you lost baby Mario, then he would also be invisible, but he would never die - you'd never lose any star power. But, he does follow you around. If you finish the level (going through the invisible goal), then the screen blackens and the game freezes.
So, as you can see, a variety of things can happen. Beware - your game may become damaged after trying this glitch
Submitted by: SolarCloud