Continuity mistake: When Joaquin enter the bull fighting ring before Manolo's bull fight, Joaquin removes his cape and drops it on the ground. When Joaquin's horse gallops by and Joaquin grabs onto his steed, the cape is missing. (01:35:00)
Continuity mistake: When the WABAC machine is going through the time vortex, trying to escape from the black hole, some tiles get sucked off the WABAC, but in the next shot they are back on.
Continuity mistake: After crashing the pig drawn car the characters fall onto a train car, the rail car directly behind the one they fall on is open and carrying barrels. In the very next scene none of the characters have moved, but there is now an enclosed train car there. (00:35:25)
Continuity mistake: During Stoick's funeral Hiccup first shoots an arrow towards the ship and then the other characters draw their bows. Gobber is not shown as he is further away. In the next shot where they shoot their arrows, Valka and Eret are suddenly further apart from each other and Gobber has moved closer in between them. Eight arrows are shot simultaneously, but only seven arrows rain down.
Continuity mistake: When Surley is in the tree getting ready to lower himself to the nut cart, after dropping Buddy in the bucket, he puts a spool of thread onto a small branch and there is nothing else on the branch. Next shot, there is a clothespin on the branch behind the spool that he moves to the front to hold the spool in place.
Continuity mistake: Just before seeing Principle Celestia, and they are walking down the hallway, the cutie mark on Sunset's shirt disappears.
Continuity mistake: In the scene at the college where Callaghan asks to look at Hiro's Megabot, Callaghan's shirt is blue, but when he holds out his arm to take Megabot, his shirt sleeve is red. Later on he is wearing a red shirt at the SFTT. (00:13:30)
Continuity mistake: When Classified is telling the penguins about the North Wind as Skipper eats the Cheesy Dibbles, the amount of cheese powder on Skipper's feathers differs between shots.
Continuity mistake: After cutting through Black Manta's gun, Aquaman then slams Manta in the face with his trident and knocks him down. As he is twirling his trident in victory, you can see his belt and its design. But then it cuts to a close up of Aquaman and suddenly his belt changes in design with the bar in the middle disappearing and the black of his pants extending further up onto his orange shirt in the belt area. (00:03:50)
Continuity mistake: Briareos' VTOL fires all of its forward missiles twice. (The forward missile bays have distinct markings in the form of a set of three white rectangles at each side). (01:15:26 - 01:16:40)
Continuity mistake: Tinker bell and her friends throw their swords on the barrel to defeat the pirates with their powers instead. The swords disappear in the next shot of the barrel.
Continuity mistake: When we first see the male volcano, he is an entire island with trees and forests. After many years have passed and sinks into the ocean, it can be seen the trees and forests have now gone. However, after he spews out of the ocean and is together with the female volcano, the male volcano suddenly has trees and forests around him again.
Continuity mistake: During the "Perfect Puppy" silly song, Bob places a newspaper he had been reading on the couch beside him when Larry starts singing. When Bob shows Larry the picture of the dalmatian, the newspaper has vanished. When the shot cuts back to Bob, the newspaper has returned. (00:16:55)