Mortal Kombat (Game Boy)

Mortal Kombat
Developer: Probe Software Publishers: Acclaim Entertainment (US/EU), Acclaim Japan (JP) Platform: Game Boy Released in JP: December 17, 1993 Released in US: September 1993 Released in EU: 1994 This game has unused playable characters. This game has unused text. This game has a prerelease article

Mortal Kombat, now in laggy, miniaturized, four-color form. Hooray?

Unused Characters

Johnny Cage

The GameShark code 010085D6/010086D6 changes 1P/2P to Johnny Cage, a character not implemented in this port. Nothing present of him except his name in the game resources, as none of his graphics are present (he uses Sonya's sprite just by accident).

He doesn't have his shadow kick, split punch, or a fatality, but he does have a fireball projectile that is identical to Shang Tsung's in the game.

(Source: Paul Courtney (BSFree))

Playable Shang Tsung

GameShark code 010885D6 will replace Player 1 with Shang Tsung. He has no moves, but can move back and forth. Pressing Up or Down causes his sprite to disappear. This player not intended to be playable at all and used only as a final boss with it's specific abilities to turn to another playable characters. This hack is nothing more than a manual corruption glitch.

Unused Text

Debug Leftovers

There are about 300 bytes of code at the beginning of the ROM (up to $000400, where the actual game data starts) that are a code/data leftovers from some kind of developer's boot monitor. It was used at the RAM-based cartridges (it does write system reset vectors manually) and intended to establish connection with some host machine vial link cable and execute remote commands. Portions of code are disabled, also there were a font someday now filled with garbage bytes ($0003C6-$0003FF). The only visible evidence of it is a routine to display the system messages on boot which contains two strings currently unused: at $000328 is

BOOT OK.

shown when boot start and at $00033E is

RAMTEST FAILED !

right after boot message in case of one of the variables is non zero. This variable $DFC4 never written even with the debug leftovers code anyway.

Unused Name

The game contains a secret unlockable mode where you may play as Goro himself. In this mode all player names and some other in-game texts has its counterparts and changed to developer names of the original MK. Even if name "CAGE" does not used in the game, it also has a counterpart: "JEAN" which is also never used in the normal game. Two string libraries containing all names and other used words for both modes are stored at $001A31 and $001AB2 respectively in ROM.

Regular strings	Goro mode strings
CAGE KANO RAYDEN KANG SCORPION SUBZERO SONYA GORO TSUNG MATCHES PAIRS MATCH MIRROR BATTLE PLAN	JEAN BOB ERIC CARL PETER GARY FERGUS GORO EDDY MATCHES PAIRS MATCH MIRROR BRITTLE PLUM