Ms. Pac-Man

Ms. Pac-Man began life as a modification to Pac-Man that its publisher had not authorised, and it ended up being the more successful game. It is also, by a comfortable margin, the best-selling arcade machine ever produced in North America.

The improvements are all in the details. There are four mazes that rotate instead of one, and the fruit bonus moves around the board instead of sitting in a fixed spot, so the safe route you memorised in the first maze does not survive into the second. The four ghosts have been reworked - Blinky, Pinky and Inky return with adjusted behaviour, and Clyde is replaced by Sue - and the ghosts now make decisions at randomised intervals, which is what stops the game from being solved by a single fixed pattern. Power pellets still turn the tables and still score in a doubling chain, and the intermissions tell a small story about Pac-Man and Ms. Pac-Man that nobody in 1982 had asked for. Namco was unhappy about the game's origin; Midway shipped it anyway, and the arcades made the decision for them.

• ▸Four rotating mazes instead of one, with moving fruit bonuses
• ▸Ghosts that randomise their decisions at set intervals
• ▸Sue replaces Clyde as the fourth ghost
• ▸The best-selling arcade cabinet in North American history