There are two sets of gold, silver, and bronze keys for both teams and there are two doors. What lies behind those two doors is unknown, but both sets of keys will unlock either door, but not both.
You obtain keys by winning challenges and the first team to win all three keys will have their pick of the doors. The other team will be able to open the remaining door when they have collected all of their keys.
More details to come when the first team gets all their keys.
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