Super Mario Bros. : The Lost Levels is the initial sequel to the original Super Mario Bros. game, and was released as Super Mario Bros. 2 in Japan. It uses the original Super Mario Bros. engine, with additions such as weather, character movements, and more complex levels, altogether yielding a much higher difficulty. The game follows the same style of level progression as Super Mario Bros. , with eight initial worlds of four levels each. The last level of the eight worlds is a lava-filled castle that culminates in a battle against Bowser. At that time, this sequel was not released outside Japan since Nintendo of America did not want the Mario series to be known to players outside of Japan for frustrating difficulty. It remained inaccessible to a steadily broadening market of American video game players, becoming stylistically outdated by the time the Japanese Super Mario Bros. 2 could be eventually delivered to America. The game later debuted outside Japan in 1993 as "Super Mario Bros. : The Lost Levels" in the compilation cartridge titled Super Mario All-Stars for the Super Nintendo Entertainment System (SNES). The original Famicom version was released for the Wii's Virtual Console service in September 2007, listed as "Super Mario Bros. : The Lost Levels" outside Japan. A later Super Mario All-Stars Wii port, titled Super Mario All-Stars 25th Anniversary Edition, features the SNES gameplay and adds Wii Remote, Classic Controller, and GameCube controller compatibility.