Enter "keepitsteady" on the cheat menu.
Unlock All Videos
Enter "digivid" on the cheat menu.
Moon Gravity Cheat
Select "Cheat Codes" at the options menu, then enter "noforce" as a code. You can also get this code if you complete all 129 goals.
Enter "letitslide" on the cheats menu.
Unlock Gene Simmons and Secret Level
Complete the Story Mode on Normal difficulty to unlock Gene Simmons from KISS and the "Hotter Than Hell" level. (In this level, find and grab the floating KISS letters to unlock a new video. You don't have to collect them in order. Collect the letters again to watch the band perform "God of Thunder" on the virtual stage.)
Unlock Iron Man
Beat the story mode to unlock Iron Man from Marvel comics.
Unlock School 2 and Venice
First, beat the game on beginner. In the New Jersey level, go to the train station. Where the rails are at, on the left ramp in the middle column there is an item high above the ramp. Take the rail down to the ramp to get more speed so you can reach the item. (Or, climb on top of the awning which looks like a little white ledge, and walk along it and around the corner.) Get the item to unlock the School 2 level.
First, beat the game on normal. In the Hawaii level, find the tiki statue. Jump into its mouth and ride down the tunnel to the end. Get the item to unlock the Venice level.
Beat the story mode on sick difficulty to unlock T.H.U.D.
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