Party Animal/Ipso Fatso/Don't Yank My Chain - S1-E2
Other mistake: Don't Yank My Chain: In the close-up of Cub after the train exits the tunnel, the window to the left is slightly open. There are blood splatters right above the glass, but since there is no glass there, the blood splatters are bizarrely floating in mid-air. (00:20:52)