During the song, It Was a Really Good Choo-Choo Ride, when Uniqua sang the line: "I'm happy that the Tsar is glad this was the best he's ever had." and Pablo sings: "I'm just relieved we made it back. And the train still on the railroad track. I left my bag, I did not stop!", throughout those words, Uniqua's antenna are not seen.
Pablo wears an ushanka for the second time.
This is the second and final episode to start with the title "Catch that--", after Catch That Butterfly.