The Night of Miguelito's Revenge - S4-E12
Other mistake: The sandbag that almost falls on Pike and West splits wide open upon impact with the floor, but subsequent shots of the bag show it almost intact.
Urutora sakusen dai ichi gô - S1-E2
Other mistake: When Bemular holds submarine 516 in its mouth, submarine 516 becomes submarine 16. (00:18:40)