Character mistake: After Pronto warns Mario of the path being a trap, Mario says that he earned an A plus for unclogging drains in the Brooklyn Plumbers Academy. However, in "Plummers Academy", he actually flunked out of the academy along with Luigi. (00:09:29)
The Adventures of Sherlock Mario - S1-E18
Character mistake: When showing the sign for the Retro Router, it misspells router as "reuter". (00:08:11)
Butch Mario & the Luigi Kid - S1-E3
Character mistake: When Mario notices the sign for free food, the sign for the sheriff misspells it as "shpriff". (00:11:00)
Character mistake: When the Koopas chase Mario and Luigi, the sign says "COOPA ISLAND" instead of "KOOPA ISLAND." (00:06:39)
Character mistake: When Koopa is chased by a cop, he passes a Burger Shop. The sign says "BURCER SHOR" instead of "BURGER SHOP." (00:04:35)
Character mistake: The title card says "Plummers Academy" instead of "Plumbers Academy."