GM Mode
Do GM Mode 2 player, and do no matches all the way through until No Way Out, where you start doing matches for 1 brand only. Then GM Mode takes about 45 minutes this way, you get Unlimited EXP, 100Gamerscore and it's effortless.
P.S Do not forget to do Advertising Promo, or you will not have enough money to hire wrestlers come No Way Out.
We have more cheats and tips for this game here, WWE SmackDown! vs. RAW 2007 cheats
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