Actually a conversion kit instead of a fully "new" game, Pac-Man Plus was developed and distributed by Midway as a set of hardware components to incorporated into existing Pac-Man cabinets. Said components modify the base game.
Pac-Man Plus makes the following changes:
- Maze walls are now green instead of blue
- Ghost behavior is modified to increase their speed and simulate more aggressive AI routines.
- Ghosts have been redrawn as shorter sprites with flowers sprouting out of their heads.
- The various bonus items have been replaced as follows
- Round 1: A definitely licensed image of a Coca-Cola can
- Round 2: A purple adult beverage
- Rounds 3-4: A goya, or bitter melon
- Rounds 5-6: A red apple
- Rounds 7-8: A bunch of red grapes
- Rounds 9-10: A Galaxian
- Rounds 11-12: A sliced loaf of white bread
- Rounds 13+: A short stack of flap jacks, also known as "pan cakes"
- Eating a Power Pellet triggers one of five events at random:
- All four ghosts turn blue, aka default Pac-Man behavior
- Three ghosts turn blue while the fourth remains in default state, but immediately reverses direction
- The maze walls turn invisible but pellets remain for the duration of the pellet
- The maze walls and pellets all turn invisible for the duration of the pellet
- The ghosts turn invisible, but are also in their "blue state" for the duration of the pellet
- Upon eating a bonus item, the ghosts all turn invisible but also enter the "blue state" until they begin to flicker white. While in this state after eating a bonus item, their point values are doubled (400, 800, 1600, and 3200 points in sequence).
The ultimate goal of these changes was to decrease the reliance on pattern memorization and increase the randomness of the game.
Pac-Man Plus was distributed by Midway to arcade operators in 1982. Bandai Namco, from whom Midway had obtained license to distribute Pac-Man, more or less abused this license in the development of this "game", alongside Ms. Pac-Man, Baby Pac-Man, Professor Pac-Man, and Jr. Pac-Man.
Bandai Namco has released Pac-Man Plus for mobile platforms and for Jakks Pacific TV Game units.
Pac-Man Plus is a bonus game included by Opcode Games in their ColecoVision homebrew Pac-Man Collection cartridge.