I never really played much Advanced Dungeons & Dragons, mostly because I didn't know there wasn't such a thing as "Beginner's Dungeons & Dragons".

Nevertheless, there were a few games that were released for the NES, like DragonStrike, which is a game where you take a dragon around and blow stuff up.

But what if you went to the copyright screen

And then pressed

Up, Right, Down, Left, Up, Up, Down, Down, Up, Down, Left, Right

Then the game would reset, and with the exception of the copyright screen, the rest of the text in the game will be in Japanese

And to reverse the effect, you either turn the game off and back on, or do the trick again at the copyright screen.

Now, why you'd want to if you didn't know how to read Japanese?

Well, you probably wouldn't.