If you want to talk about a true "Hidden Gem" Sonic Adventure Limited Edition is the rarest U.S. released game. It features a different disc, manual, & back art. The in game menus are different the games sounds and animations are also different then the standard copy. By far the Holy Grail of U.S. Dreamcast collecting. It was a Hollywood Video rental exclusive 3 months b4 the Dreamcast was released, all copys were suppose to be destroyed.