Original URL: http://www.psxextreme.com/ps2-cheat-print/291.html
Rainbow Six 3

Cheat Stage Select:

On the main menu, press START to access the Campaign, Custom Mission, Split Screen, etc. choices. Enter L1, R2, L2, R1, D-PAD LEFT, D-PAD RIGHT, SQUARE, CIRCLE.

You should be able to select any map in custom mission mode (and play the practice missions on any difficulty). 

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