Mega Man ZX
|Mega Man ZX|
There are unused colored sprites of Model O in the game.
The game itself uses a browned-out variation of one of the sprites, and the semi-Biometal itself is named "Mysterious Stone".
Though Model O is not obtainable in easy mode, using cheats to obtain it will use these sprites when Vent or Aile are saved from bottomless pits by the Biometal. This implies that Model O may have been intended to be obtained by defeating Omega in easy mode.
Upload the sprites.
Omega has some leftover frames of animation that were originally used in the final scene of Mega Man Zero 3 after he had been defeated. These can't be seen in-game without modifying the ROM.
The game contains several card keys, each with a color, but one of them, "White Card Key", is unused. Its description is "It doesn't take a genius to figure out this opens white doors." There are no doors that require its use.
The game contains a debug room with several features for testing, which include normal surfaces, walls that can't be climbed, a slippery floor, a moving floor, a sinking area, one ladder, water, and spikes. The room can be accessed with the Action Replay code, 22160484 00000000.
The Japanese version has all plot-relevant discussion with NPCs voiced, with full voice-acting. All of the other versions remove it completely. Also, all of the Japanese-language battle cries used during gameplay by the titular character (Like "Rock-on!" at every costume change), and most of the bosses' battle cries before their introduction are removed (with the exception of Promotheus/Pandora, and Omega).
The "Rock On!" text on the title screen is also removed in non-Japanese versions of the game.