Continuity mistake: Season 4, episode 10 "Ben 10 vs. The Negative 10, Part 2": When the Forever King makes his announcement "Nothing will stop this little home-coming", he stands outside the Mount Rushmore base on bare soil. But in the scene where Max reviews the recording of this speech, all of a sudden we find the Forever King standing on a neatly tiled floor.
Continuity mistake: Season 4, episode 9 "Ben 10 vs. The Negative 10, Part 1": When Charmcaster waves her good-bye to Gwen just before Animo swoops her up, the coloration of her waving sleeve's decor suddenly changes from violet to purple.
Revealing mistake: Season 4, episode 5 "Ben 4 Good Buddy": When the Baron drives off from the garage in the Rust Bucket, the VR's interior shifts unnaturally; an obvious glitch in the computer animation.
Continuity mistake: Season 4, episode 9 "Ben 10 vs. The Negative 10, Part 1": When Charmcaster taunts Gwen about not having "taken off the training wheels", she moves her head upward. Note that the lower part of her ponytail falling over her backside does not move as the upper part does, but remains fixed in place.
The Krakken - S1-E3
Continuity mistake: When The Krakken snatches the Cannery crate from the boat, you can see that the lower horizontal bar from the 'E' is suddenly missing, thus reading 'Cannfry'.
The Krakken - S1-E3
Continuity mistake: When Ben pretends to be sucked into the lake, and Gwen turns around to look after him saying "I'm not falling for it", she's missing her eyebrows for a second or two.
The Krakken - S1-E3
Audio problem: When the kraken roars, when it destroys a ship, it sounds like a TIE fighter in Star Wars.
Continuity mistake: When the three old people throw the car at Ben and Gwen, Ben doesn't have the Omnitrix on for a few seconds. (00:14:10)
Continuity mistake: When the Marty-alien removes the dumpster as Ben watches him, there is a set of stairs leading down. But later, when Ben (as Wildmutt) and Gwen jump down the shaft, the stairs are gone and there is an iron ladder.
Continuity mistake: The number of rockets Sixsix has on his wrist launcher alternates between three and four, especially during the final combat scenes.
Deliberate mistake: When Sixsix impacts with the ground due to Greymatter sabotaging his jet pack, the furrow he ploughs into the ground is already present when he skips across the ground.
The Alliance - S1-E8
Continuity mistake: When Rojo attacks the police academy, there is a patrol car right behind her. But when Ben (as XLR8) arrives and slams into her, the car suddenly vanishes.
The Alliance - S1-E8
Plot hole: After Upgrade has successfully removed Rojo's cybernetic parts, the beam rifle she had used in the armoured car heist at the episode's start suddenly appears among them. But when the drone merged with her, she wasn't holding the gun and so it couldn't have been transformed along with her.
Lucky Girl - S1-E10
Plot hole: When Hex revives in the ambulance, the stone to the right of the glowing Reincarnation Charm is the Luck Charm - which Gwen has at that time. Therefore it should be missing from the necklace, but there it is.
Continuity mistake: When Ben is upset because he is too short to go on the water slide, he is wearing a bathing suit. But in the shot where the Omnitrix deactivates and he is back to being a human, he is in his normal uniform.
Deliberate mistake: When the Tennysons drive towards the city's power plant, Grandpa Max is using the left side of the highway instead of the right. Even with a looming nuclear accident, correct traffic habits do play a role, especially on such a narrow highway. Who knows whether one might drive down the road in a hurry and you approach him on his side of the highway?
Other mistake: When the Tennysons drive towards the city's power plant, Grandpa Max is using the left side of the highway. Curious, since you drive on the right in the USA - regardless of the looming nuclear accident there was no reason to invite a crash like that.
Revealing mistake: It is strange that the news coverage at the beginning of this episode is able to cover the story from all angles in such rapid succession: from the helicopter straight to the ground, then even a close-up of the goon atop the crystal mount Diamondhead traps him on.
Continuity mistake: When the Tennyson's RV passes by Rapid City when it comes under attack by Vilgax, it's the first time the outskirts can be seen. But later, when the gas station explodes, the entire town is suddenly hidden behind a mountain range.
The Big Tick - S2-E2
Factual error: When Gwen and Grandpa Max use the shell plates from the tick to ward off it's corrosive secretions, their fingers should have been eaten away since they were grabbing the rims of the plates when the acid came raining down.
