Inca - The Mayan Adventure

Skip to Mayan Temple:
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Press [F1] at the restore game screen. The password to
skip the first twelve levels will be displayed.
Cheat mode:
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Enter one of the following codes to activate the
corresponding cheat function.
Effect               Code
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Display next save password - [Left Shift] + [Right Shift] + [Esc] 
Instant kill enemies     - [Ctrl] + [Alt] + Fire
Full power           - [Shift] + [Ctrl] + [Alt] 
Full lives and power     - [Shift] + [Ctrl] + [Alt] + inca
During dogfights, you can renew your energy by pressing :
[Ctrl]+[Alt]+[LeftShift].
Somebody brought us code 31148226. 
Not much, but a starter…