Here is a little bit of background information on the Nintendo World Championships – it happened to be a custom game which was specially developed for a nationwide Nintendo Entertainment System (NES) tournament that took place nearly a quarter of a century ago – 1990, to be exact. There were only 116 cartridges produced, where the custom game would require players to beat select levels from popular titles such as Super Mario Bros., Tetris and Rad Racer in less than seven minutes. After completing these levels, scores were tallied and winners would be sent to the national championships, where 90 semi-finalists picked up a free copy of Nintendo World Championships. Needless to say, these have become extremely rare today as you can tell by the crazy auction figures alone.