On the main menu, there are two crystals: a green one and a red one, here are the combinations available:
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- Xray (girls are nude):
[green, green, green, red, green, green, red, green, green, red]
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- Instant-Text (text is displayed instantly):
[red, green, green, red, red, red, green, red, green, green]
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- Scanlines (retro-filter):
[green, red, green, red, green, red, green, red, green, green]
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- Lucky-Dice (instant win gambling game):
[red, red, red, green, green, green, red, red, red, green]
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Those cheats are not disabled by exiting the game, you need to type the cheat code a second time to disable it.