The Nintendo Super Famicom was released in Japan on November 21, 1990. It was the successor to the Nintendo Famicom and was Nintendo's second home console system. It was designed by Masayuki Uemura, the maker of the original Famicom, and was an immediate success, selling 300,000 units in less than a day. As a fourth generation console, its main competition was Sega's Mega Drive (the Sega Genesis), but Nintendo quickly established itself as the leader in the home console market. Part of its success was due to the retention of several major third-party game developers, such as Capcom and Konami. In 1991, Nintendo released a redesigned version of the Super Famicom, the Super Nintendo Entertainment System (SNES), for the North American market. The console shipped with the immensely popular game Super Mario World, and has since sold 23.35 million units. Along with the Mario and Donkey Kong franchises, the Zelda series proved to be paramount to the Super Nintendo's success. In 1991, Nintendo released The Legend of Zelda: A Link to the Past in Japan. One year later, it found a home in the North American market. The game, spearheaded by Zelda creator Shigeru Miyamoto, tells the tale of a boy named Link and his quest to save the mythical world of Hyrule from the devious villain Ganon. A Link to the Past introduces Agahnim, a fiendish wizard who strives to free an imprisoned Ganon. This entry in the series was significant for introducing many new elements to the Zelda franchise; the Master Sword, the ocarina, the hookshot, and the spin attack were all introduced in this installment. Additionally, The Legend of Zelda: A Link to the Past was the first Zelda game to contain parallel universes in which the character travels between. The Light World was the standard overworld of Hyrule. The Dark World, however, represented a sinister reflection of what could happen if Ganon managed to conquer Hyrule. The Dark World is the result of what happened to the Sacred Realm - home of the Triforce, a triangular item that contains the essence and power of the Goddesses who created Hyrule - when Ganon obtained the Triforce and ravaged the lands. The parallel universe theme was further explored in The Legend of Zelda: Ocarina of Time and The Legend of Zelda: Twilight Princess. The Legend of Zelda: A Link to the Past sold over four million copies, making it one of the highest grossing games of all-time for the Super Nintendo.