Complex X is a platform arcade game, released by P.G.D. (Progressive Game Distributors) in April 1985; it was the last game to run on the altered version of Taito's Qix hardware first used for Space Dungeon, The Electric Yo-Yo, Kram, and Zoo Keeper (two Motorola M6809s run at 1.25 MHz and a Motorola M6802 run at 921.6 KHz, with an added Motorola M68705 run at 1 MHz). The game was originally going to be released by Taito America, but the company never released it because they closed down their manufacturing plant in September 1984. However, the game still credits Taito America and has a 1984 copyright date on the title screen. The player must use two eight-way joysticks (one for moving and one for firing) to take control of a nuclear scientist whose objective is to escape from a flooding reactor as the water's level rises below him before running out of air (which is indicated by the "AIR LEFT" meter at the top of the screen) - and every blue-and-magenta square he collects shall add ten shots to his reserve (indicated by the number above the "AIR LEFT" meter that starts at 50 for every level), which he must use to shoot creatures that block his progress. Like Mario and Luigi in Mario Bros., the scientist may also disappear off one side of the screen and reappear on the other, but to make him jump, the player needs to push a button on top of the "firing" joystick (and good timing is essential for reaching the moving, magenta platforms); furthermore, once the scientist reaches the level's exit, he will receive a bonus of 100 points for every shot remaining in his reserve.