Revealing mistake: When Vic Frohmeyer excitedly tells the kids that Mr. Krank is putting up his frosty, the kids turn their attention away from their video game and get up to leave, but the video game continues to be played, indicating the video on the screen is a recording. (00:59:20)
Revealing mistake: You can see Hero Boy putting the ticket in his pocket after getting it punched the second time, before finding his seat on the return journey. However, the ticket slowly evaporates in the air as he is about to put it into the pocket. His hand thus enters the pocket ticket-less.