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LEAD TO ROME    All tracks 
MAD HOOKUP      All upgrades 
SAD CLOWN       All divisions 
TURN TRICKS     Stunt mode 
YOKOZUNA        Sumo mode (bigger collisions) 
ZAKARY X        Unlock all codes

Thanks to Revolution readers AHAMMER99, Cody Gannaway, keith, Brian Sled, Imran Mohammad, and Mitchell Jones!