A box containing nearly 100 rare Nintendo games was found, and inside were copies of a previously unknown version of Super Mario Bros. and Duck Hunt for the original Nintendo Entertainment System. I mean, I had Super Mario Bros. and Duck Hunt growing up; what makes these so special? READ MORE: Illinois Video Arcade is Largest in US With Over 885 Free Play GamesWhat Makes These NES Games So Rare? Here's how these found games are different: they feature different everything, like different labels, different screws, different manuals, and different motherboards. READ MORE: Vintage Video Game Arcade with 100+ Free Play Games Now Open in WisconsinWhy Old Video Games Could Be Worth a FortuneWhile that sounds like a lot of money, a rare copy of Super Mario Bros. previously sold at auction for a whopping $660,000.