Type the following case-sensitive DOS command: SET INVOKEDEBUGMODE=TRUE. Then, enter the game directory and run the program by typing "DS". Now a cheat menu will appear after the game loads.
If you want to finish the game go to file and choose the two player mode. There you will have another plane but your score will be change to "zero".
Everytime you blow up, go to file and resume last. It will give you your life back at the same spot where you clicked file.
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