When Baydool is teaching T to fire a blow dart, Baydool's moustache disappears.
The bulge of stuffing reveals how the arrows are standing in Baydool's chest.
Baydool uses the word "blueprint." Printing with blue paper, hence the name blueprint, was not invented until the 19th century.
Archimedes, who lived during the second century BCE in Greece, is shown with a book with a stapled binding which contains a prophecy that only makes sense in English.
When Baydool first brings Tee to his house, some plastic hangars with costumes on them can be seen in the background.