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Continuity: The beer that the guys make from the stolen recipe is a reddish-brown color. When the Wolfhouse brothers begin to bottle and sell the beer, the beer is in light green bottles. The beer inside the bottle is not reddish-brown, or else the bottles would have looked darker when full. The unopened bottles look like there's a light-colored beer inside of them.
Revealing: When the American and German teams are playing a drinking game involving putting coins into glasses while downing pints, the camera switches to an angel at the end of the table. If you look at the front two people's hands, they are going past the pint glasses, and the coins are disappearing, yet the pints are still filling up with coins.
Deliberate "mistake": In the scene towards the end of the movie where the Americans are preparing to face the Germans in the all boot double or nothing challenge, when they are shot from the side there are 10 boots on the table. In the next shot when we see the American team face on, only the Americans' 5 boots are still on the table. Then when they go back to the side view in the next shot all 10 boots are back on the table.
Visible crew/equipment: When everyone gets together in the beer training place and the guy says "Lets drink some beer" watch his face and you will see the shadow of something that looks like a camera. (Don't get it confused with one of the guys arms or mugs, if you look where the shadows come from you will see).






