First, you need find the right edge of any room, where the screen stops scrolling but you can still proceed to the next room. It has to be a passage that scrolls when you pass through it, and not one that fades to black. Now, turn into a ball. Move to the right like you're going to the next screen, but at the last possible pixel and second, move back to the left. When done correctly, you'll scroll to the right and notice that a column of blocks is much different. Instead of the screen stopping, it keeps scrolling to the right. It should eventually lead into very glitchy areas, a.k.a. Secret Worlds.

There's just one small problem... You can't stop the scrolling. It will eventually cycle back to where you started again, and keep on going in a loop. This is an excellent way to sort of "explore" some places, but you can't move around anymore. You'll have to reset the game in order to play again.

It's difficult to do with a Gameboy, and is guaranteed to take several tries. If you use an emulator (available at Zophar's Domain) with a Metroid 2 ROM, however, it's pretty easy.

If you have any problems with this trick, remain persistent. Keep in mind that it works best as a ball, and you have to hit the left button exactly before the screen begins to scroll.

(View Screenshots)