Ms. Pac-Man (NES, Tengen)

Ms. Pac-Man
Developer: Tengen Publisher: Tengen Platform: Unlicensed NES Released in US: 1990 This game has unused code. This game has unused graphics. This game has a hidden level select. This game has a Data Crystal page

Tengen's port of Ms. Pac-Man for the NES is, surprisingly, a much more faithful port than Namco's own port, despite being released three years earlier. This particular port was ported to the Genesis in 1991, which was then ported to the SNES in 1996. Port port port.

Unused Graphics

Unused MAZE tiles, similar to the used LEVEL tiles that are used for the level counter in the HUD, probably supposed to be used for a maze layout number display.

Unused dot and pop effect graphics found among sprite graphics in the game.

These graphics are defined among Act 4 cutscene animation frames of Pac-Man and Ms. Pac-Man going into the background. Using Game Genie code APUOUPAG will extend their movement to show these unused frames.

Level Select

Pause the game, then input the following button code: A, A, A, B, B, B, Up, Down, Left, Right. When you return to the options screen, you will be able to select any level higher than 7, up to 30.

Additionally, if you instead input: A, A, A, B, B, B, Up, Down, Left, Right, A, B, A, B, A, B, Up, Down, Left, Right, B, A, B, A, A, A, Up, Down, Left, Right, you will be able to select levels up to 99! The Select button can also be used to instantly skip to the next level.

Unused Power Pellet Functionality

The power pellet gives a variable amount of power time depending on the current level. However, it appears that the power pellet was supposed to give no power pellet time in Arcade maze selection in levels 20 and above (which would result in ghosts turning around instead).

Due to a programming oversight, this behavior is never encountered. The relevant code that handles this can be found at the ROM address $958A and it looks like this:

LDY CurrentLevel                    ;if in levels 20+
CPY #19                             ;(note that it's value+1, so 0 = level 1, 19 = level 20, etc)
BCC @NoCap                          ;

LDY #18                             ;fix range

@NoCap:
LDA Options_MazeSelection           ;check if in non-arcade mazes
BNE @NonArcadeTimes                 ;

LDA PowerPelletTimes_EFA1,Y         ;
CPY #19                             ;checks if in level 20+
BCC @SetPowerPelletTime             ;

LDA #$00                            ;this would give 0 power pellet time
...

The code first checks if the player is in level 20 or above and caps the index for power pellet time. However, an identical check is encountered later, after checking for Arcade maze selection.

Since the cap value is always less than the level check value, the game never gives the player 0 power pellet time, resulting in the same behavior as if the player was in Mini, Big and Strange maze selections.

Easter Eggs

Tunnel Easter Egg

In a two player game, if both players enter a tunnel and collide with each other at the same time from inside the tunnel, a Junior will spawn from atop the Ghost House and roam the maze. Up to six Juniors can be spawned and each Junior can be picked up for 5,000 points.

This easter egg can be triggered on levels 10 and upwards, and once triggered six times, no additional Juniors will spawn. The easter egg does not exist in the Genesis, SNES, or Sega Master System versions of the game.

(Source: Game Manual)

Inverted Controls

Pause the game, then hold Select and B. When you unpause the game, your controls will be inverted. This can be reverted by pausing the game again and holding Select and A.

(Source: Game Manual)

Unused Level String

Located at 0x1CC6 in the ROM is an unused string.

LEVEL

Unused code in the ROM suggests this was originally a level counter before it was replaced by the graphics that appear in the bottom edges of the screen (in all maze sets except for "Arcade").

(Source: RussianManSMWC)

Oddities

Extra Life Scoring

In all maze sets, a total of four extra lives can be obtained per game. Here is a table of the extra life scores shown below.

Extra Life	Arcade	Mini, Big, or Strange
1st Life	10,000	10,000
2nd Life	970,000	50,000
3rd Life	980,000	100,000
4th Life	990,000	300,000

Humorously, instead of adding a check to disable multiple extra lives, the "Arcade" maze set sets the remaining 3 extra life scores to over 970,000 points, a score normally unachievable without cheat codes, since all maze sets end after 32 stages. This was most likely done to simulate the Arcade game only giving one extra life per game.