Ms. Pac-Man is an unofficial sequel to Pac-Man, which has become part of the official franchise. The arcade game was released in 1981 in North America and became one of the most popular arcade games of all time.
The game began as Crazy Otto by General Computer Corporation, who had just settled a lawsuit with Atari over their Missile Command conversion kit, which updated the game to Super Missile Attack. Part of the settlement terms forced them to get consent from the original game manufacturers before releasing new conversion kits. Crazy Otto was based on the original Pac-Man, so GCC presented the game to Midway who distributed Pac-Man arcade cabinets in North America. Midway had been long awaiting Namco's Super Pac-Man release, and saw the potential in Crazy Otto. They bought the rights, rebranded the game as Ms. Pac-Man, and changed the sprites. At the time, Stan Jarocki of Midway stated that the name and character change was a thank you to the original Pac-Man for being the first commercial video game to have a large female fan-base.
The success of the game sparked many legal battles between GCC and Midway over royalties, but the game was eventually turned over to Namco who held all rights to the game and characters. Though Namco has treated the game as the black sheep of the series, saying they had nothing to do with it, GCC co-founder Doug Macrae has stated that then-Namco president Masaya Nakamura approved the project and had even provided feedback over character artwork. Namco continues to publish Ms. Pac-Man on its anthologies, but makes little mention of it anywhere, including within extra content in those anthologies which provide historical context for all games the within.
The game stars Ms. Pac Man, and follows the gameplay of the original title where the player moves around a maze trying to avoid the ghosts chasing them while they eat all the dots on the screen. Power pellets allow Ms. Pac-Man to eat ghosts and temporarily disable them. Levels contain fruit bonuses and increase in difficulty as the player moves through the game.
Ms Pac-Man features several updates including 4 new maze designs, two warps tunnels, random enemy movement instead of movement based on the preset rules used in the original Pac-Man, new sound effects, and fruit that move around the maze instead of staying in the center.
The game also features three new intermission scenes following Pac-Man and Ms. Pac-Man, including an appearance of their baby, Pac-Jr. Also, the orange ghost's name is changed to Sue instead of Clyde.
Ms. Pac-Man was widely ported and received a Mini-Arcade tabletop version by Coleco. It's also included in many Atari collections for consoles and stand-alone joystick controller arcade collections. As part of Pac-Man's 30th anniversary, it is one of the games included on the home version of Pac-Man's Arcade Party arcade machine, and is an unlockable minigame in Pac-Man 2: The New Adventures(SNES/Genesis) and Pac-Man World 2(PS2,Xbox,Gamecube). Ms Pac-Man was also bundled with every Xbox Live Arcade disc for the original Xbox. A 360 XBLA version and iOs version were also released.
The NES, SNES, Master System and Genesis versions of the game developed by either Tengen or Williams featured additional updates by including four different sets of mazes. Players could choose from the original arcade mazes, bigger mazes, smaller mazes, and "strange" mazes. A boost button was also added which allows Ms. Pac-Man to move faster, and two player modes are available where player 2 controls Pac-Man. These releases end at level 32 and feature a fourth intermission scene as the ending.
The NES version of the game published by Namco did not feature any of the additional features.