Cheat Codes:
The cheat used in KKnD (original) for 32 mil in oil credits can be used in KKnD Xtreme as well, here it is again:
KKND & KKND Xtreme Save Game Oil Cheat
A cheat to get heaps of oil credit in KKND or KKND Xtreme
Begin a level and then save the game. Use a hex editor - I use XTGOLD - In XTGOLD highlight the saved file and then press V for view, H for Hex, E for edit. After you have edited the hex press enter, Esc and quit XTGOLD. Now go back to KKND/KKND Xtreme and restart your saved game. In the Survivors levels the first line of your hex will look something like this:
000000 0100 0000 0000 0000 0000 0000 0000 0000
Regardless of the numbers that may be in your saved game change this to:
000000 0100 0000 0000 0000 F301 F301 F301 0000
This will give you over 32 million oil credits.
In the Mutants levels your hex will look something like this:
000000 0200 0000 0000 0000 0000 0000 0000 0000
Change this to: 000000 0200 0000 0000 0000 0000 FFFF FFFF FFFF
This will give you a negative oil figure with the result that you will never run out of oil credits.