When Mikey says he wants a tattoo of himself so he can wear it as a mask, his face from Teenage Mutant Ninja Turtles (1987) appears.
Sab Shimono, who voices Mr. Murakami, had previously played the villainous Lord Norinaga in Teenage Mutant Ninja Turtles III (1993).
Amongst the weapons that appear in this episode is the jitte, a Japanese martial arts trucheon, as seen imbedded in the punching bag Leo's seen using after sparing Fong.
Donatello mentions in passing that he suspects he and his brothers were mutated from either diamondback terrapins (Malaclemys terrain) or common box turtles (Terrapene carolina), the two most common pet turtles species in North America.
Splinter mentions about a Daimyo in the 16th century.