Klax was commercially released in PAL regions, however, the NTSC version was never commercially released. As a result, this track requires the use of a Harmony Cart or other approved removable, erasable ROM storage device with the correct Klax NTSC ROM installed. Multicarts of any kind are NOT ALLOWED, as the player must produce the MD5 code of the ROM used upon request. Difficulty switch positions have no effect, and therefore can be left in either position. Player must choose Wave 1 from the starting menu, however, after completing Wave 1, players may choose the 5-Drop option to skip levels thereafter when offered. Secret warping is allowed.