Transylvanian Homesick Blues - S2-E65
Character mistake: Ray says that it's the very first time they've dealt with vampires. In Season 2 Episode 25, "No One Comes to Lupusville", the Ghostbusters had to deal with both werewolves and vampires.
There's No Place Like Home - S28-E16
Character mistake: The old photo of Sylvia and her friend shows them in RAF uniform. Sam, who is a serving British Army officer and could be expected to recognise the very obvious differences between the uniforms, keeps referring to Sylvia being in the Army and Sylvia does not disagree with her.
Character mistake: During the radio show, the radio host gives the radio station's phone number as 555-4455, Alf then softly repeats the number back before he gets to the phone. He then picks up the headset and dials a number, but the numbers he presses on the phone don't match up to the number given by the radio station. (00:04:10)
Doragon! Muteki no ken to tate - S1-E4
Character mistake: Shun says explicitly that a Saint's body is no different from any ordinary human's. That's quite funny, considering that in the previous episode Hyoga fought creating temperatures of -100 °C (consistently, to defend himself, and aggressively to freeze Ichi), which would have messed up really badly both contestants.
I'll See You in Court - S5-E20
Character mistake: Charlene says Rocky was nominated for 9 Oscars, it was actually nominated for 10 but in 9 different categories.
The Singer - S7-E5
Character mistake: Near the end, Matlock says that he can prove who killed KC. The burden of proof lies with the prosecution; as a defense attorney, Matlock doesn't have to prove anything.