What would cause two Nintendo games to get switched?

[WA]

My friend and I played his landlord's Nintendo (like the original deal) for the first time last weekend and we found something surprising. When we inserted the Zelda cartridge, the game Duck Hunt came on, and when we inserted Duck Hunt, Zelda came on. The cartridges looked real and untampered and we had the boxes from them also. Is this a rare occurrence? How could this have happened?? If it's really rare, I'll put the video I took on youtube.

 

[BDOLE]

There are quite a few ways to do this. The typical NES cartridge is made up of a plastic casing around a 72-pin board. The board is the only part necessary to play the game, but the plastic casing is used in order to protect the board from damage. With a few basic tools, it's a simple task to take apart the plastic casing and switch two boards between cartridges.

Another trick would simply be to obtain a sticker label for another game and place it over the original label, or remove the original label and replace with the new one. That's actually a bit harder, those stickers are almost impossible to remove in one piece and obtaining/making a new one is more difficult than taking apart a cartridge.

Think of it like if you put the entire CD case in a system to play a CD so there was no point taking the CD out, except in this case, somebody did. It's a little harder than that, but not much.

 

[Lankey]

its quite easy to take out the circuit board from inside a NES game and swap them around without any obvious evidence of tampering. Maybe it was someones idea of a practicle joke.