The clock will run down, and then...

The second tribute to enter Crocodile Creek will discover what appears to be a watch. Upon further inspection, they see that the face of the watch has the numbers zero through twenty three around the edge instead of one through twelve. There is only one hand on the watch, which is pointing toward the number that matches the current number of dead tributes. If the tribute chooses to keep the watch, they will see that this hand updates accordingly.