Character mistake: Another identity mistake in the finale: When Beast Boy's team is initially subdued, we see honorary Titan Hot Spot standing amongst the villains even though he is a) a hero and b) is supposed to be frozen solid at that time.
The Calculus Affair: Part 2 - S1-E13
Character mistake: After reaching the border, Snowy finds an umbrella and Tintin states that it is Calculus's umbrella. It isn't Calculus's umbrella - Calculus's umbrella has a brown handle, and this one has a grey handle. (00:42:25)
Character mistake: In the third instance where Superman manages to get rid of Mxyzptlk, he uses an article full of typos which spell the latter's name backwards as KLTPZYXM. Among the incorrect words is the word "citrimes", in which Superman has included an I and a T, so the correct word in context with the rest of the text should read "crimes" and thus the errors would spell KL-I-TPZYXM. Since there are no vowels in MXYZPTLK, however, what is the additional I doing here - and why didn't Mxyzptlk bother to mark it as a mistake, either?
The M.O.D.O.K. That Time Forgot! - S1-E2
Character mistake: M.O.D.O.K. refers to Hoobastank as "the Beatles of the late 90's." Hoobastank only released one album in the 90's, and they didn't become popular until after they released their second album in 2001.
Character mistake: Despite being a Greek mythology buff Maxie Zeus says "Vulcan" when he meant "Hephaestus" the Greek god of fire and the forge when he first spoke with Batman.
Mystery on the Prarie - S3-E14
Character mistake: If Chris and Martin are creature experts, they would have already known the buffalo birds are nest parasites.
7 Continents for 7 Koopas - S1-E22
Character mistake: When Mario and his friends are trying to unclog the pipe, Toad says for the Mario Bros. to pull the plunger, but they are initially pushing it instead. In the same shot, Mario's brown hair turns black. (00:05:57)
Character mistake: Throughout the series, General Ross refers to Gabe Jones as Gabriel. Someone of Ross' military credentials would not address another government agent by their first name. He would call him Agent Jones or simply Jones.
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)
Character mistake: Bessie's last name is misspelled "Higginbottom" on the newspaper Happy shows her.
Champion vs. Creator, Part II - S1-E27
Character mistake: Pegasus says his toon world cannot be penetrated, but that is not true since it's a magic card, so any card that destroys magic cards can destroy it. Furthermore, monster special effects can also destroy it.
Character mistake: When Cheryl, Pam and Alan Shapiro are talking on the movie set, the store behind them has a typo: Stationary should be spelled "stationEry'. (00:10:30)
Takishîdo wa kaze ni mau - S1-E1
Character mistake: During Lucky's initial display of power at the gates of the settlement, he fires a cannon shot at the building and shouts (in the English dub) "How do you like that? Bullseye." There's a view of the building and you can read the horseshoe sign; "Evergreen SHOPING Mall." (00:07:15)
Adventures in the Elements - S1-E12
Character mistake: On the Hexside brochure, Principal Bump is misspelled "Principle Bump." (00:00:03)
Invasion of the Ferb Snatcher/Ain't No Kiddie Ride - S2-E28
Character mistake: In 'Ain't No Kiddie Ride' Carl reminds Major Monogram that he has no sense of smell and that he was born without nostrils noting it on his resume. But in 'Brain Dead' when Major Monogram sees Perry wearing a face mask he points out that Carl is also a germaphobe. Carl corrects him saying "It's not the germs sir, it's the garlic smell." He wouldn't be able to smell anything since he has no nostrils. (01:10:00 - 01:35:00)
Character mistake: After Anakin says to use the walkers (AT-TEs) as boarding vessels, Rex calls the first one an AT-AT (a vehicle that does not even exist at this point in-universe) while ordering a battalion of clones into it. (00:04:10)
Six Forgotten Warriors Chapter 4: The Six Fight Again - S5-E5
Character mistake: When the Red Skull reemerges from the vortex, he sees Chameleon and acknowledges him as his stepson. However, only moments before this, Kragov explicitly stated that the Chameleon was more like an adopted son to the Red Skull.
Character mistake: Professor Saotome checks the status of the Getter Robot when his son falls unconscious. The HUD output is written in awkward EngRish, from the first line of the status report, called; "Monitor the state of affairs", to smaller details like the article randomly used for certain lines ("a control device, a correspondent"). The biggest flub though is that the name of his son is "Tatsuhito", in proper romanization, but here appears as "Tatuto." (00:05:20)
The Prison Prep School Murder Case File 1 - S1-E10
Character mistake: To show how hard the top students are working at the prep school, we see one of them writing; "I was at the course of a eight-week intensive." (00:04:50)
Character mistake: Lucy Liu-bot says Fry's name normally, but uses an automaton voice for "Can eat more", when she has always used Fry's name as a Text-to-speech type of automaton voice. (00:07:45)