Type in codes:
Press Alt, S and F simultaneously on the title screen to activate a menu item in the configuration menu (Sound Effects Test). This will let you cycle through all the action sounds in the game and listen to them.
Normally you can only select difficulty levels from Punching Bag to Champion, but there is a hidden difficulty level named Deadly (For One Player Mode Only). To get this difficulty level, keep pressing the right arrow key even though it is on the Champion level already. Deadly will show up after about 20 key presses.
There is also another secret difficulty level even above Deadly level named Ultimate level (For One Player Mode Only). To let you select this level, press the O, M, and F keys simultaneously.
While playing, press and hold the B, I, and G keys and any number from 1-9 (where 9 is the most) to increase or decrease the amount of scrap falling off a robot when hit.
To change the colors of your robots in 1 or 2 player mode, just go to the robot selection phase and hit the 1, 2, and 3 keys to change the color of the first robot, and the 4, 5, and 6 keys to change the color of the second robot (do not use the keypad keys).
Debugging:
NOTE: In all the editing below, there appears to be differences in the registered and unregestered versions. As always, be sure to back up your files before editing them!
Byte 27 of the .chr file control your ranking, which you can do some pretty amazing things with. In the North American yournament, you start in 11th place. If you set your rank below this, go into the sournament, and go into the arena, you will find a sercet character to fight there. You can enter the arena over and over again to fight the same secret character. Don't forget to remember your old rank so you can set it back when you are done.
NOTE: Sorry, I will not list moves here, they do not fall into the catagory of cheats. If you are interested in moves, find one of the OMF Faqs.