Other mistake: On the police blimp, the scanner/radar screen in close-up has a single white circle, but in the wider angle it's two black circles, which are even hand-drawn and thus not perfect circles. (00:01:30)
Other mistake: Batman is reading the front page of the newspaper, but in the drawings that follow, the paper is right-most, it opens to the left of the page. Gotham is not in Japan. (00:04:50)
Other mistake: When Batman listens to the tape left behind by the security guard (and the police's incredibly sloppy investigation) he presses play and not only the tape is at the right point without him having to rewind, but the recording is much different from the actual events and gives him a convenient abridged version. (00:08:00)
Heart of Ice - S1-E3
Other mistake: When the children interrupt Summer Gleason's news report to play in the snow, the two police officers on the right are completely motionless for the entire 15-second shot. (00:02:10)
Heart of Ice - S1-E3
Other mistake: When Batman is watching the security footage of Victor Fries' accident, at first Fries is addressing the camera directly which follows him and pans according to his movements and Ferris Boyle interrupting him, which would suggest a second person was in the room with a handheld camera. But after Ferris Boyle enters the room and orders Fries' experiment terminated, there are several cuts from various angles in the room suggesting surveillance cameras. The surveillance style footage also often conveniently cuts to the face of whichever person happens to be speaking or will cut to a certain angle in order to put emphasis on the action, all of which would require multiple mounted cameras and purposeful editing by either Boyle or one of his subordinates, which would be completely illogical since they don't want anyone to see the footage in the first place. (00:12:20 - 00:13:55)
Heart of Ice - S1-E3
Other mistake: Batman uses a thermos full of chicken noodle soup to defeat Mr. Freeze, and moments later gives Summer Gleason a security tape that incriminates Ferris Boyle. When Batman pulls out both of these aforementioned items, there is a corresponding clicking sound that suggests he pulls them from his utility belt, but both items are far too large to fit inside the belt. They also could not have been simply been hanging from his belt, as Mr. Freeze had possession of Batman's belt a few minutes prior and they were not there. (00:20:05 - 00:20:45)
Other mistake: After the level crossing, the back of Stromwell's car is missing entirely the fender or any sort of lights. It's a close-up, even. (00:05:45)
Other mistake: Batman leaps off a tall building carrying Stromwell and lands on one foot without breaking the fall. (00:12:25)
Other mistake: The Stromwells are hugging in front of the office building, but that was the starting point 5 minutes before, there has been a long chase since. (00:21:15)
Other mistake: Melissa Manchester and Neil Ross voice minor characters in this episode. The end credits list them like this though; "Additional Voices - Melissa Manchester as Neil Ross." It should have been "And", of course. (00:21:55)
Other mistake: At the beginning of the fundraiser for the university, people drop in a basket cash and cheques. All the bank cheques though have the sum written in the wrong format; for instance "five thousand dollars" is written "5.000.000." (00:12:30)
Other mistake: The Scarecrow and his goons escape on an airship, which has the control bridge in the gondola under the main structure. Batman reaches the top of the airship, and so does Anthony the goon...but he does it from a trapdoor on the roof of the gondola. There's a whole structure in between he skipped. (00:15:10)
Other mistake: Gordon has some impressive ceiling fan in his office, since not only one of its blade supports a full-grown adult hanging by the back of the neck to it, but it even keeps working as usual during it. (00:21:30)
Be A Clown - S1-E11
Other mistake: The cards that Jekko the Jokester throws at Batman have in one shot ("Now it's my deal") numbers that do not match at all the symbols. (00:13:40)
Be A Clown - S1-E11
Other mistake: When Jordan comes out of the truck, something went wrong with perspective and/or proportions, because with his leg bent he is practically as tall as the truck door, and he's a child.
Other mistake: At the beginning of the episode, the truck of the "Gotham Globe" delivers to the newsstand a nice bunch of copies of the newspaper, which naturally bears the name..."Gotham News" (00:01:20)
Other mistake: Batman's lungs have plot armor; he has all the time to put his mask on even after exposure to the gas, and he reacts to it coughing at first. Nobody else in the episode reacts with a cough. (00:07:55)
Other mistake: Several shots during Harvey Dent's fundraiser show characters in the crowd never blinking or moving a muscle. (00:07:10)
Other mistake: The eyebrow on Two-Face's left side is completely illogical. He wouldn't suddenly have an eyebrow that's bigger and bushier than his other eyebrow, and if anything the explosion that created Two-Face would have singed off that eyebrow. The eyebrow is there when the doctor removes Harvey Dent's bandages, so it's not like he put a fake one on for cosmetic reasons, nor would it make sense for the doctor to put a fake one on ahead of his face being surgically repaired. (00:21:15)
Answer: She escaped off-screen and created a copy of herself to fool everyone.