Plot hole: When Vlad enters Mehmed's tent, the entire floor is covered in silver coins and Mehmed remarks on Vlad's weakness to it. There's no way that Mehmed could have known about Vlad being a vampire or about his weakness to silver, as Vlad had killed every Turk after becoming a vampire, so nobody would be alive to tell him. Even the Turk found on the battlefield in the morning lived long enough only to deliver Vlad's message, but died immediately after that.
Continuity mistake: A couple of scenes after the baker's wife ripped off most of Rapunzel's hair, it has grown back to full length so that the prince can climb up to the tower on it.
Visible crew/equipment: When the doctor wants to study Electro, a green screen and some other things are reflected in his glasses. (01:14:10)
Continuity mistake: In the shot before Josh hands in his preregistration sheet, he is not wearing his cross necklace around his neck. It was in shots prior to that, and is the focal point of the scene with the preregistration sheet. But in the shot where he is just walking, his clothes and all are the same, but no necklace. (00:03:30)
Continuity mistake: Azog kills Fili with his arm sword, running him through from back to front. In the next moment, when Azog tosses the dying Fili off the ledge, we see the arm sword - and it is shiny, clean and spotless.
Factual error: When Magneto enters RFK stadium, a groundskeeper is lining a baseball field. RFK stadium did not host baseball in 1973, as the Washington Senators had moved to Texas to become the Texas Rangers after the 1971 season. In 1973, the only team playing in RFK regularly was the Washington Redskins of the NFL. In addition, the Paris Peace Accords were signed in January of 1973; so there wouldn't be green grass inside the stadium, regardless of what sports were being played there.
Factual error: In the rat revival scene, Dr. Terra Wade, an electrophysiologist, demands that the other scientist, Dr. Bell increase the current, going as high as 200 joules. However, current is measured in amperes (amps), joules is a unit of energy.
Continuity mistake: When Max is on the train, after finding out about the stitcher, he's next to a poster ad that has people in it. After the shot of the couple kissing, the poster ad has changed to just having words on it. The person standing next to the seats changes too, and then in the final shot is gone. (00:21:55)
Other mistake: Zarina creates orange pixie dust that is supposed to give you light bending powers. But when Zarina throws the dust on the fairies and they change powers, Rosetta ends up with orange which gives her animal powers, not light bending powers.
Revealing mistake: Crawling through a fire cave you can see propane bottles in the background several times.
Continuity mistake: When Thomas first arrives at the Clay Pits, Timothy can be seen with a train of trucks. In the next scene, they have disappeared.
Character mistake: At the end of the movie, when Jaggu is listening to the sounds recorded by PK, the audio contains the question which she asked, "Tumhare planet pe sab aise hi hote, bade kan wale?" but does not contain the answer which PK gave, even though he was sitting right there. This seems to suggest that PK did not exist in the real world.
Continuity mistake: Near the end, Thomas is saddling a horse. He throws the stirrup over the saddle so he can cinch the girth. But he is interrupted by the presence of the witch he loves. Somehow, the horse has had its girth cinched and the stirrup is in its proper place, all without Thomas' help.
Continuity mistake: When the crocodile catches the man he bites his right foot off. 5 seconds later as he falls into the water his foot is back. (01:21:05)