Errors/Ben 10: Ultimate Alien

Fame

 * When Ben wakes up, Rozum has green eyes.
 * When Ben got out from the water his shoe is miscolored.
 * Towards the end of Ultimate Spidermonkey's transformation, if you look closely, the muscles on the right of his body are gone for a brief moment.
 * When Ben as Ultimate Spidermonkey wrapped up Bivalvan, his knee was sticking out, but when it showed him fully wrapped up, all of it was in the web.
 * After Ben reverted back from Spidermonkey, Ben's eyes glow pink for a moment. According to Charlotte Fullerton, the glowing eyes were an animation error.
 * In one scene, when Ben was about to go to school, his backpack was brown. Then in the next scene, his bag turned to the same color as Julie's (light blue).

Duped

 * Rath somehow has a phone.
 * When sensitive Ben opens his eyes, the white part is black.
 * When arrogant Ben steps out of the bathroom, the black 10 emblem on his jacket is white and the 10 is in black text.
 * When Kevin absorbs metal, it was the same color as stone.

Hit 'Em Where They Live

 * In some scenes, Charmcaster's eyes are blue.
 * The establishing shot of Mr. Smoothy has Gwen and Sandra both holding Smoothies, but in later shots, Sandra's Smoothie has all but disappeared.
 * When Ben transformed into Big Chill, Big Chill's hologram is not shown on the Ultimatrix.

Video Games

 * When Four Arms grabs Ssserpent's arms, it's with his upper arms. When the camera changes angles, it's with his lower arms.
 * When Oliver is talking to Harangue after the video game scan, his voice is the same as the one he used when he was talking to Ben, but later in the series, it changes.
 * When Jetray sits on the top of the minivan after stopping it from falling over because of the Stalker, the black zigzags from the Ultimatrix to his shoulders are missing, then during the same battle while Jetray shot his lasers and they were reflected, the zig-zags are gone again during Jetray's close-up.
 * When Cannonbolt opens his mouth, it is blue instead of black.
 * Gwen's driver's license has Gwen Tennyson written on it instead of Gwendolyn.

Escape from Aggregor

 * In the scene where the Yeti smashed Four Arms into the ground, the golden bands on his chest were black.
 * Ultimate Big Chill had red legs for a second.
 * When Aggregor lands on Aldabra, he has holes on his stomach.
 * When Galapagus is hit by Aggregor, his mouth is green.
 * When P'andor and Andreas are walking away to go take over the ship, Andreas' tail is missing.
 * After Galapagus sends a distress call, he turns around to see Aggregor subduing Bivalvan and Ra'ad, there's an Ultimatrix symbol on Galapagus' chest.
 * When the aliens were looking at Aggregor as Prior Gilhil was murdered, Galapagus' eyes were all black.
 * When Aggregor attacks Andreas, Ra'ad, Bivalvan and P'andor and they jump in a hole, P'andor's feet are miscolored.
 * When Aggregor turns around, Ra'ad disappears.
 * When Galapagus attacks the Aggrebots, the cracks on his shell are transparent.
 * In Fame, Ben was not able to turn into any alien before the Ultimatrix had scanned Bivalvan, but in this episode he scanned Galapagus only at the end.
 * When all of the aliens' holograms are shown:
 * Swampfire, Goop, Cannonbolt, Way Big, Wildmutt, Nanomech, Water Hazard and Four Arms are missing.
 * When Terraspin's hologram is shown, he has white eyes instead of green.
 * Rath's neck was orange instead of white.

Too Hot to Handle

 * Even though there was a sound of the containment suit getting pierced, the suit was still intact until Kevin was tricked into actually opening it.
 * When Humungousaur went ultimate, the flash was blue instead of green.
 * When Ben goes inside the nuclear reactor, he spins the Ultimatrix symbol until it's sideways. However, when he hits it to turn into Big Chill, the symbol is no longer sideways.
 * After Ben turns into Big Chill, the Ultimatrix symbol is no longer red (indicating radiation) even though P'andor was still there.

Andreas' Fault

 * In multiple scenes, Jetray's stripes on his torso are lost.
 * When Argit said "I have other plans", he sounded like Gwen.
 * When Argit was going to ring the bell, the bell rang before he pressed the button.
 * When Andreas first appears, his arm is floating without connecting his body.
 * Argit had two jacket stripes after the castle's collision.

Fused

 * When Ben selected Brainstorm, his hologram didn't have his brace.
 * In the end, when Ra'ad battled Aggregor, in one scene his eyes were seen red.

Hero Time

 * The crowd standing changed from a cluster line into a single file line. This occurred both at the booksigning and at the party.
 * When Ben becomes Spidermonkey, the fans are standing in front of the cordon, even though they were standing behind it before the fight.
 * Spidermonkey flies on top of the building across the street. However, is actually the same spot where Captain Nemesis puts on his armor, but he is not seen.
 * Various other errors occur during the first fight:
 * Although both of Jennifer's bodyguards are shot and fly backwards, they disappear throughout the fight and even when Jennifer kissed Ben.
 * The fans at the booksigning appear and vanish throughout the fight.
 * Jennifer and the thug who keeps her at hostage constantly vanish and appear.
 * The guns vanish after the thugs were being disarmed and beaten.
 * The Darkfall poster on the door appears and vanishes throughout the fight.
 * Ben mentioned that he has a poster of Captain Nemesis on his wall but all of the many episodes his room appeared in his poster wasn't seen.
 * Kevin mutes the volume on the TV when he, Gwen, and Julie are watching the news about Bennifer. However, when Ben arrives and watches Harangue's news, the volume is automatically unmuted.
 * When Gwen hits Kevin, his face and hand are merged.
 * When Jennifer was talking to Ben by the helicopter the stripes on Ben's sleeves are on both sleeves.
 * When Jennifer says "Ready for the party?" to Ben, Gwen and Kevin vanish when the camera moves from Julie to Ben.
 * When Ben was at the party, his jacket stripes are on the wrong side.
 * It stops raining within a second.
 * When Jetray dives, his chest stripe is yellow.
 * When Nocturne begins hosting for the friendly contest, her shorts are black.
 * Humungousaur's feet appeared before Ben transformed into him.
 * When Ben and Nemesis are having their race one of the placards the fans are holding reads "I <3 BEM".
 * When Captain Nemesis arrives at the finish line, the audience is reused three times.
 * The bridge in the race vanishes when Captain Nemesis beats Rath in the race.
 * During the competition, in one scene, the N on Captain Nemesis chest was miscolored.
 * After Captain Nemesis loses the competition, one of the audience members doesn't have a face.
 * When Ben enters the Nemesis Tower, his jacket stripes are on his left sleeve instead of his right sleeve.
 * When Captain Nemesis shot a rope at Ultimate Humungousaur's arm, the rope on his arm disappears for a split second and reappears in the next scene.
 * When Nemesis is flying towards Ultimate Humungousaur, his horn is green.
 * Right when Water Hazard takes his first swing at Overlord, the N on his chest is missing.

Ultimate Aggregor

 * When Ben uses Ultimate Big Chill to keep the fans away, the Smoothie he set down disappears
 * The emblem on Ben's jacket has its black and white colors interchanged, one of the most common errors of the series.
 * Kevin says his badge used to be his dad's. However, Kevin took the badge from Magister Labrid after Labrid died.
 * After Lodestar revives himself, Ben tells Gwen "for what it's worth you were right about the trap thing" when Max is the one who said "it's a trap!"
 * When Nanomech says the line "You can't beat us all." his mouth doesn't move.
 * When Gwen blasts Aggregor, the Entropy Pump misses the energy.
 * When Humungousaur strikes Aggregor, his lips are brown.

Map of Infinity

 * On many scenes, Humungousaur didn't have black lips.
 * When Aggregor blasted Gwen, she didn't have a face.
 * The Necrofriggians suddenly appear on the bridge.
 * When Ben transformed into Big Chill, the Ultimatrix's colors were reversed.
 * When Big Chill was talking to Gwen, the sides of his Ultimatrix symbol are white.
 * When Big Chill was talking to one of Necrofriggians, his Ultimatrix was missing.
 * When Big Chill tackles a Necrofriggian, he doesn't have the Ultimatrix.
 * When Ben first turns into Ultimate Echo Echo, he grabs his shoulder disks. Yet, after he takes them off, the right shoulder disk is still there. In the next scene, it's gone.
 * When Ultimate Echo Echo attacks the second Necrofriggian his left eye misses its stripe.
 * On most of his scenes, Ultimate Echo Echo has a blue bar or doesn't have the circle symbols on his back.
 * When Ultimate Echo Echo is flying on top of the acid, his fingers are blue.
 * Ben's jacket stripes appear on the wrong side in one scene.
 * Ben was burnt on the right side of his face; yet, when he's lying on the ramp, his right side is facing the icy half of the planet.

Reflected Glory

 * When Four Arms goes into the Forever Knights hideout, just as the smoke clears Four Arms' bottom gold straps are gone.
 * In one scene, Four Arms' underwear is gold and only has three arms.
 * Kevin's metal form changes between two colors.
 * When Psyphon made the entrance through the roof, Ben was shown wafing off the dust. The next scene showed Ben as Four Arms, switching back to human form.
 * When Spidermonkey transformed to Ultimate Spidermonkey, he sounds completely different than he was supposed to.
 * Ultimate Spidermonkey's jaw is miscolored on many shots.
 * When Psyphon attacks Ultimate Spidermonkey, his energy beams disappear.
 * When Psyphon lifted Ultimate Spidermonkey, he was much smaller than he should have been.
 * Oliver claims that the webcast is live, but after Cash accidentally gets knocked out by the Forever Knight, he claims they can "save it in editing."

Deep

 * At the beginning of the episode when Magister Pyke is chasing Ultimate Aggregor, there's a lot of rocks shown floating around. But later in the episode, there aren't any rocks at all, excluding the core.
 * When Ben and Kevin leave the Rust Bucket 3, most of Ben's body merges with the water and the ship.
 * When Pyke attacks the fish, his whiskers have outlines.
 * When Ben transformed into Humungousaur, the palms of his hands swapped between the color of his stomach, and the color of his back and arms.
 * When AmpFibian came out of the water, the highlights of the water were green.
 * When Pyke got his water helmet, Kevin was shifting between his normal form and his metal form.
 * When Pyke grabs Gwen, his angler is grey.
 * The Piscciss Volann guards had grey anglers.
 * When Big Chill is chasing Aggregor, two Piscciss Volanns start to chase him, for a moment it can be seen that the one on the right has Magister Pyke's design.
 * The whole time Goop was pulling the planet together, Pyke did not have his helmet on and yet showed no discomfort.
 * Kevin says "S'ok, I took pictures" and displays a cell phone but when he and Gwen rescued Ben, he did not take pictures.

Where the Magic Happens

 * At the start of the episode when Aggregor was being chased by Four Arms, Gwen and Kevin, Four Arms' lips were outlined in black.
 * When Charmcaster defeats Gwen, she says that Ledgerdomain was made of mana, though Charmcaster didn't know about mana until Gwen explained it to her later in the episode, but she understood what Gwen meant.
 * After Gwen asks Charmcaster to help them enter Ledgerdomain, Charmcaster turns around and her tiara is colored light purple instead of black.
 * Charmcaster's eyes change between light blue and purple throughout the episode.
 * The ledge where Charmcaster hears Spellbinder's voice is shown as a well-like hole when Charmcaster almost steps off.
 * When Humungousaur hits the Pallorfang, its eyes disappear.
 * The surroundings of the Door to Anywhere changes at the end of the episode.

Perplexahedron

 * When Gwen was frozen she had her mouth open in the next scene she had both her upper and lower teeth joint together.
 * When Cannonbolt becomes Ultimate Cannonbolt, the Ultimatrix doesn't gain the four spikes until after the transformation is finished.
 * The last piece of the Map of Infinity keeps vanishing and reappearing.

The Forge of Creation

 * For a split second, Terraspin is missing a hole on his body.
 * In the scene in time barrier, Gwen's collar was red instead of white.
 * 10 year-old Ben's Omnitrix contains an error. The button used to activate the alien selection dial is on the wrong side of the Omnitrix, facing outwards. The button is supposed to face towards Ben for ease-of-access and has mistakenly been put on the outside.
 * When Kevin is introducing himself to young Ben, the part of the jacket between the two shoulder stripes of Ben's jacket is black instead of green.
 * When 16 year old Ben is first talking to young Ben his jacket is shown to have stripes on either side.
 * In the scene where young Ben is looking through the Ultimatrix, it is colored like the Omnitrix.
 * When both Bens used Four Arms, 16 year-old Four Arms' eyes were miscolored yellow.
 * When 16 year-old Four Arms is about to change 11 year-old Four Arms, his hourglass symbol is grey.
 * When Ultimate Aggregor throws young Four Arms into the air, before he hits 16 year-old Four Arms, his eyes are miscolored green instead of yellow.
 * When Ultimate Aggregor throws young Four Arms, his Omnitrix symbol is on the wrong shoulder.
 * When Ultimate Aggregor reaches for the baby, he uses his left hand. However; in the next scene he is reaching with his right.
 * During the battle with Ultimate Aggregor, Kevin is shown running away. The next time he is shown, Kevin's knocked out despite not actually fighting Ultimate Aggregor.
 * When Ultimate Kevin grabs Ultimate Aggregor's head, before absorbing his powers, his Rath claw is the same color as his left arm and hand, and also changes to Armodrillo's armor color when he shoots Jetray's neuro blasts right in his face before he absorbed his powers.
 * When Ultimate Kevin jumps to fly away from the Mother Celestialsapien, his legs are blue along with his pants.
 * When Gwen kisses young Ben, his Omnitrix looks different.

...Nor Iron Bars a Cage

 * In the hospital, Ben had a white sleeve.
 * When Kevin 11 reverted to his human form, his shorts were blue instead of brown.
 * When Goop goes under the door of the room he and Gwen were locked in, the Anti-Gravity Projector gets there before the door is even opened.
 * In the scene where Armodrillo tackles Ultimate Kevin, Ultimate Kevin's appearance is reversed.

The Enemy of My Enemy

 * When Ben is talking to Gwen in his car, he loses the stripes in his right sleeve.
 * When Ultimate Kevin talks to Argit, his eye misses its outline.
 * In the scene where Ben, Gwen and Argit are discussing where they're going to hide Argit, Gwen's collar was red instead of white.
 * The episode keeps switching between Argit's jacket having a line on either side and having one line on the left side.
 * Coronach's eyes differ between black and grey.
 * One of the Plumbers mouth disappears when he is done speaking.
 * As Humungousaur turned into Ultimate Humungousaur, the 4 spikes are not popping out of the right sides of his Ultimatrix symbol.
 * In some scenes, when Ultimate Humungousaur is fighting Ultimate Kevin, the Big Chill hood is not on his head.
 * In the scene where Ultimate Echo Echo was flying, one time he has light blue colored feet, like his shoulders, and another time he has blue feet like his regular skin.
 * One one scene, Coronach's sclerae were green.

Absolute Power: Part 1

 * While Ultimate Kevin absorbs Alan's powers, his Spidermonkey arm is brown.
 * After Ultimate Kevin absorbed Alan's abilities, Alan's Plumber Badge disappears.
 * When NRG grabs Kevin's arm, his Ultimatrix symbol is missing.
 * After turning from Way Big to Ben, the floor turned back into cement even though NRG melted it into lava, which can't of cooled down in that time.
 * When Gwen raises a mana shield to protect herself from Ultimate Kevin's mana attack, it cracks before the attack hits it.
 * Gwen couldn't have summoned Stone Creatures, as they only followed Charmcaster because she freed them.

Absolute Power: Part 2

 * At the beginning of the episode, during the recap, Ben says "Previously on Ben 10: Alien Force instead of Ben 10: Ultimate Alien. This has been corrected on the DVD release.
 * Ultimate Kevin's hood disappears, from when he landed into the building, to when he arises from the wreckage of the second building. He briefly gains it again in between in some scenes only.
 * At the end of the episode, the height ratio of Kevin to Ben and Gwen was bigger than usual.
 * After Kevin is restored and Darkstar is defeated, Max says "Heatblast and the others" when referring to Alan, who does not go by Heatblast.

The Transmogrification of Eunice

 * After the escape pod that contained Eunice opened, some parts of the green smoke didn't move for a while.
 * When Ben transformed into Spidermonkey, his torso was colored standard blue.
 * On one scene's the outlines of Sunder's mouth had the same color as his teeth.

Eye of the Beholder

 * When Ben transforms into Jetray and Brainstorm, he has the Omnitrix on his wrist, rather than the Ultimatrix.
 * During Jetray's transformation, the Omnitrix is green in one scene and black in the next.
 * On one scene, Ship has light green highlights.
 * During Baz-El's Heimlich maneuver, Julie's hand is green instead of black.
 * When Julie gives back its eye to the sentinel, Baz-El has green lines on the green parts of his body.
 * When Swampfire transforms back, Baz-El shortly had a green line instead of a black one.

Viktor: The Spoils

 * When Ultimate Echo Echo showed up, his voice is lighter than normal.
 * In one scene, Big Chill's hands are colored blue instead of black.
 * When Big Chill unfolds, the Ultimatrix's colors are reversed.
 * When King Xarion was in the dungeon, he had shackles on his wrists and ankles. However; even though Gwen only breaks the shackles on his hands, he walks away without freeing himself from the shackles on his legs.
 * When Gwen breaks King Xarion's shackles, the whole bar shatters. However, in another scene, the bar is shown to be twisted.
 * When the king experiments on an unconscious Ben, there is a grey bar in front of Ben's lower body, but in the next moment it's gone.
 * When Heatblast punched Viktor into a tank, the Ultimatrix symbol appears larger than normal.
 * There is no conceivable reason that the soldiers' equipment should break or shatter, just because Ben turned off the mind control function.
 * When the gang walks away during King Viktor's speech, you can hear him say more without moving his mouth.
 * Kevin says in this episode that Plumbers can only arrest aliens but Dr. Animo reveals in the episode It's Not Easy Being Gwen that he was held by the Plumbers.

The Big Story

 * When Jimmy is being chased by Plant Humungousaur, his jacket kept switching from zipped to unzipped.
 * When the Plant Alien shoots the liquid that forms a sort of containment around Swampfire, it shoots a lot of the liquid (enough to almost drown Swampfire) but after it turns into the barrier there is only the part around Swampfire.
 * When the plant picked up Swampfire the Ultimatrix symbol was missing but in the next scene it re-appeared.
 * When Ultimate Swampfire is telling the others to run away, his eyes were like Swampfire's.

Girl Trouble

 * On one scene, Sunny's eyes are green.
 * In the transformation of Four Arms, in one part he has four fingers on each hand.
 * On one scene, the Ultimatrix's rim was black.
 * In one scene, the black ten emblem on Ben's jacket is white and the 10 is black.
 * Lodestar's voice was higher than usual and his eyes were bigger than usual.
 * When Gwen steps on the Dimension 12 robots, one of them changed within seconds.
 * When Kevin is trying to stop the bomb from becoming more powerful, the on-off switch look alike, both set to the off position. As soon as the camera changes to a few frames before Kevin smashes the machine, one switch is set to on.
 * When Antonio throws Humungousaur, Humungousaur's toes are the same color as his scales.
 * When Ultimate Humungousaur fired his missiles at Antonio, the missiles didn't explode.
 * After Antonio is defeated, Ultimate Humungousaur's neck was blue.

Revenge of the Swarm

 * When Ben says "Incredible, simply incredible", the underneath of the Ultimatrix cannot be seen.
 * When Ben showed the Nanochip to Elena, it looked bigger than usual.
 * When Kevin and Gwen are talking in Burger Shack first, there was nothing on the table other than burger and the drink but in the next scene there is a cup there too.
 * When Julie is tied up in the closet, her hands are tied behind her back. When Armodrillo rescues her, her hands are tied in front of her.
 * In the next scene after Ben finds Julie in the closet, she is untied and ungagged, but it is impossible Ben had enough time for freeing her, moreover when he was fighting against the swarm.
 * When Elena and Julie are talking and Elena sacrifices herself, Gwen and Kevin cannot be seen fighting the Victor Validus clones behind them.

The Creature from Beyond

 * When Gwen connects to the Lucubra in the car, the seal is on the opposite side and side ways.
 * When Ben turns into Goop he is missing his Anti-Gravity Projector.
 * Armodrillo's face was smaller than usual, while his hands got bigger and his elbows didn't have jackhammers.
 * When Armodrillo and Kevin break the wall to get the Lucubra, Armodrillo yelled "Kevlin!"
 * Before Gwen creates the seal over Lucubra, she is wearing a metal helmet, afterwards, it disappears.
 * Instead of Sir Reginald, another knight who wasn't there during the seal break, becomes the Lucubra's victim.

Basic Training

 * When Ben says "Hello old friend" the circle on his right wrist is green but in the next scene it is grey again.
 * During target practice Ben is shooting at a picture of an alien, in the next slide it is a totally different alien picture.
 * When Ben says "But not as good as us" in combat practice, he was going to hit the Ultimatrix on his left hand, but there was an Ultimatrix on his right hand, too.
 * During combat practice, the Alpha Squad member who caught Kevin was the same person who caught Gwen.
 * When Hulka throws Kolar into the Null Void, one of Kolar's arms is cut off in the middle.
 * When Magister Hulka came in after their training was over, when they lined up, Ben was cross-eyed.

It's Not Easy Being Gwen

 * When Gwen put her headphones on the table, when she got out the spellbook, neither the headphones nor the MP3 were there.
 * When Gwen across the corridor, the students passing by her were a lot smaller.
 * Dr. Animo says that he was held captive by the Plumbers, even though Kevin says in Viktor: The Spoils that Plumbers can only arrest aliens.
 * When the fog clears out after Ultimate Cannonbolt was getting whipped around by the mutant frog and laying down, the four spikes for the Ultimatrix on Ultimate Cannonbolt's chest are gone.
 * When Ultimate Cannonbolt punched the Mutant Frog, the headband on its forehead was missing.

Ben 10,000 Returns

 * When Eon is hit by the time ray in the beginning, he doesn't have his cape. Also, the fire around him is gone.
 * At the beginning, when Ben 10,000 changes from Ultimate Ben to normal Ben, he still had the Ultimatrix symbol on him; but when Professor Paradox came in he didn't have it anymore.
 * In the museum, Kevin keeps shifting between human and metal form.
 * When Ben shakes hands with Ben 10,000, it is shown to be with the right hand. But when the scene changes, they are shaking with their left hands.
 * When Kevin absorbs a stone to fight Eon's Servants, the stone he absorbs is brown, but his armor is shown to be grey.
 * When Ultimate Swampfire grabbed Eon, his Ultimatrix was slightly shifted.
 * When Eon threw Ultimate Swampfire on the ground, the four spikes on the Ultimatrix are missing.
 * When Ben 10,000 takes Ben to run from Eon, his Ultimatrix symbol on his chest was gone.
 * Present Ben and Ben 10,000's heights change throughout the episode. He was shown to be only a head shorter and then later, his chest and up.
 * Ben, Gwen, and Kevin are noticeably shorter in this episode.

Moonstruck

 * It is unknown how Max's old boxes would remain as the Rust Bucket was destroyed in The Visitor and Absolute Power: Part 1.
 * When the Synthroid places Verdona into the containment pod, the bracelet briefly switches from her left arm to her right then back again when Max comes to rescue her.
 * At the end of the episode, the colors of the 10 on Ben's jacket were inverted.

Prisoner Number 775 Is Missing

 * The amount of strength that Prisoner 775 has rapidly changes throughout the episode.
 * When Ben transforms into Echo Echo, the Ultimatrix hologram pops up, even though Ben didn't touch it.
 * While Echo Echo was running away from the exploding Plumber Ship, his contour has a covered part of the Ultimatrix.
 * When Ben's team was picking up the sheriff who was knocked out, his badge changed from grey to gold.
 * When Kevin absorbs the car, his fingers are on the glass, yet he still gains a metallic layer.
 * In one scene, after Humungousaur fought Prisoner 775, Prisoner 775's spout on his body appearance is reversed.
 * When Prisoner 775 slipped from Gwen's mana shield, his teeth contours were the same color as his skin.
 * When Gwen was shielding the prisoner, Kevin was shifting between his normal form and his metal form.
 * When Prisoner 775 looked at the window of Colonel Rozum's house, it showed Rozum's Wife holding their baby who had only a white blanket over him. But in the next scene, the baby was chewing a blue pacifier in his mouth.
 * After Prisoner 775 looked at the window and Wildmutt jumped on him, he threw Wildmutt back, saying "Leave me be, I intend to balance the scales", his eyes were reverse colored, but then changed back to the regular colors.
 * When Ultimate Wildmutt was holding Prisoner 775's tail, his upper lip wasn't black.
 * On one scene, one of Ultimate Wildmutt's teeth had the same color as his tongue.
 * When the Ultimatrix was stating that Prisoner 775 was available, it was colored darker.
 * One of the Plumbers' neck was covered with his suit at one point.

The Purge

 * In many scenes, Argit's jacket stripe was brown or gone.
 * When Argit is talking to the team, Gwen's hair becomes transparent for a second.
 * When Argit grabbed a cape, it was purple but then the cape was red.
 * When the Dragon Robot was attacking, Argit stands in front of Ben. In the next scene he stands behind Ben.
 * Just like in Girl Trouble, Lodestar's voice is different, being high-pitched.
 * Lodestar's back was different than it's supposed to be.
 * On the Rust Bucket 3, Argit's ear is yellow.
 * Argit's shirt was brown when they pretended to leave the market.
 * In one scene, Ben's jacket stripes were gone.
 * When Ben says "Guess they heard I was coming", the side of his Plumber Badge turns light grey.
 * When the Forever Knights were shooting at Upchuck, he had the energy in his mouth before he was even hit.
 * When Ben said his monologue, Kevin was in his human form, instead of his metal form. Also while saying the same, he displays the Ultimatrix whose dial is much lower and smaller than usual.

Simian Says

 * There is no reason that the DNA sample in the Codon Stream should be affected if the Arachnichimps are taken over by DNAliens, as Azmuth said that the Omnitrix can even bring an extinct species back to life.
 * Even though Simian does not mention that Mizaru is a crime boss, Ben says "Are you telling me you willing brought a Xenocyte to your home world and set it loose on a crime boss?"
 * Even though the DNA sample of the Arachnichimps was not restored to the Codon Stream, Ben was able to turn into Spidermonkey.
 * When Simian was on the ground after being rescued by Kevin, he has an Ultimatrix symbol.
 * When Simian's hands were on a stone there was a mold of his fingers, but when he turns around to Ben there was no mold of his hands.

Greetings from Techadon

 * After Rath turns around to fight the Techadon Robots again, the Ultimatrix symbol briefly becomes white.
 * On one scene, Rath's arm is entirely orange.
 * The Techadon Robot manages to hit an intangible Big Chill with a pole.

The Flame Keepers' Circle

 * The flashback shows Vilgax's ship exploding in mid air despite the fact that it didn't; it blew up while in the water itself.
 * When Ultimate Big Chill says "Alright, you win." His mouth moves.
 * When Ben turned back into regular Big Chill before turning into himself, the four spikes are clearly visible on the Ultimatrix symbol.
 * When Ben is about to transform into Echo Echo the Ultimatrix seems to be turned off.

Double or Nothing

 * At the beginning of the episode, at the Burger Shack, when Kevin was eating his burger and Gwen is playing with her fries, you can see that the table is dirty because of the ketchup. But after a few seconds, the ketchup was gone.
 * When Vilgax is taking his bow Albedo's hair is shown white instead of brown for a second.
 * The scene when Albedo took off his wig and looked at Ben, his left eyebrow is touching his eye, but in the reflection of it in the mirror, it is higher up.
 * After NRG shot his nuclear laser at the Fridge, NRG's shoulders color were white instead of grey.
 * In one scene, when Ben is talking to Albedo, Ben's jacket line's on his right arm is gone.
 * When Hugh was holding NRG, NRG's helmet was as wide as his body.
 * When Hugh is talking about his celebrity status on Earth, the camera switches angles and Hugh's glasses disappear. When the camera pans back, his glasses reappear.
 * When Albedo said to Ben "I blame you!", the emblem 10 on his jacket is same color like Albedo's.
 * At the end, when the man who sues Ben is walking off into the distance, the other two men that were with him are not seen.

The Perfect Girlfriend

 * After returning from rescuing Ben from Ssserpent, Gwen is missing her stockings.
 * After Gwen returns home from the hospital, she is wearing stockings on under her cast.
 * A few seconds after Kevin threw his glasses on the ground, they were gone.

The Ultimate Sacrifice

 * Through the entire episode, Sentient Ultimate Humungousaur claws were grey instead of black.
 * Even though the Ultimatrix created Ultimate Humungousaur, Sentient Ultimate Humungousaur mentions having a mother.
 * When Sentient Ultimate Humungousaur transformed into the Ultimatrix, the black switch on the Ultimatrix was not there.
 * Ghostfreak's back line pattern changes twice.
 * Heatblast's lines on his body are different when he is in the ice.
 * Ben has an Ultimatrix even though he is inside the Ultimatrix itself.
 * Way Big was once again smaller than usual.
 * When the ultimates got out, Sentient Ultimate Echo Echo looked smaller.
 * When Azmuth was fixing the Ultimatrix, for a split second, part of his jaw was in front of the watch.

The Widening Gyre

 * In two scenes the insignia on the sleeve of Colonel Rozum appears on the right hand.
 * In one scene, the side of Terraspin's shell was the same color as his skin.
 * In one scene, when Terraspin in rapid spinning form was battling the Mutant Seagulls, his Ultimatrix symbol on his chest had no black color.
 * When the Garbage Monster changes from the island into the monster, Ben, Gwen and Kevin are close together. But when the scene changes, they appear to be far apart.
 * When Kevin grabs the Garbage Monster from behind, NRG's top is the color of his body.
 * They say that the trash island is twice the size of Texas but when they show an overhead view of the island near land, it is no bigger than the bridge it is next to.

The Mother of All Vreedles

 * When Ben receives an incoming transmission while in the Rust Bucket 3, the Ultimatrix is seen on his right wrist.
 * When Ben tricks Ma Vreedle into letting him go, the underneath of the Ultimatrix cannot be seen.
 * Octagon's Plumber Suit had a white circle instead of a grey one at the end.

A Knight to Remember

 * In one scene, one of the five Plumbers had purple eyes, instead he had black eyes.
 * When Driscoll shoots the team, his hand/gun does not move. He fires three shots to exactly the same point but the trio still collapse.
 * When Kevin and Ben are arguing about Gwen's teleportation, the wall next to Gwen is about waist height, but in the next scene it changes to about shoulder height.
 * Inside the Rust Bucket 3, the signs on the floor are dark, but in one scene they are light.
 * On one scene, Kevin isn't piloting.
 * Kevin absorbs the metal, but he becomes a different color. He switches between the right and the wrong color on several shots.
 * When Ben was defeated as Eatle, he was on his back. However, when he turns back Ben is on his stomach.
 * When Ben says "stop" to George, Gwen's collar is the color of her skin.
 * In the end credits Fasttrack's name is misspelled Fastrack.

Solitary Alignment

 * When Azmuth says to George "You think I can't?", Azmuth's black middle strip on his suit is gone. But after he said that, the strip reappeared.
 * When Ben shouts the name of Fasttrack, his mouth didn't move.
 * When George deflects Ultimate Humungousaur's missiles with his sword, the effect is more akin to deflecting bullets than explosive projectiles.
 * The credits misspell Fasttrack's name Fastrack.

Inspector 13

 * After Inspector 13 opened the garage door, Kevin's Car appears next to him.
 * When Gwen appears in Kevin's garage she has a sweat band on her left wrist then when Kevin tells her to power up, the sweatband is gone.
 * After Inspector 13's ship arrived, Echo Echos' rackets were gone.
 * After the ship lands, the net disappears, and not only does an Echo Echo disappear, but Julie is also on their side. In the next shot immediately, the second Echo Echo disappears.
 * In one scene, when Julie was punching the ship, the door was gone.
 * Inspector 13 says "No one has seen us and lived". He said this although he knew Kevin and Julie had tried fighting him and survived.
 * When Ben is strapped to the torture table, the position of the shackle on left hand keeps changing. For a while, the Ultimatrix is partially inside the shackle, then it comes out and goes back in.
 * Several times, Kevin's armor changes color.
 * When Diamondhead is falling there is no back diamond.
 * When Rath tears off head of Techadon Robot, there are four fingers on Rath's head.

Enemy of My Frenemy

 * When Gwen casts Liberatio, the background within her hair is white.
 * After Kevin had talked about teaming up with evil guys never ends well, Ben mentioned Dr. Animo, Darkstar, Connor, Vilgax, and Charmcaster. Ben and Gwen had teamed up with everyone but Dr. Animo.
 * In one scene, Ben's jacket stripes are on both sleeves.
 * In one scene, Eatle's back fin has a green line on it.
 * When Spellbinder reprimands Charmcaster for what she did to get him out, the magenta circle on his chest was missing.
 * In the end of the episode, while Ben lifts both his hands saying 'who's up for a smoothie?', the Ultimatrix is missing.
 * In the credits, it misspelled Dagon instead of Diagon and Addwayta instead of Adwaita.

Couples Retreat

 * When Ben is reading the spell and shows the page to Gwen, it is empty.
 * When Kevin and Ben are talking about Charmcaster beating Darkstar, the thickness of Ben's shoulder stripe changes.
 * Gwen's Spellbook was missing the gold outline on the cover.
 * When Jetray was talking, he only had three top teeth.
 * At the end of the episode, Charmcaster's collar was entirely black.

Catch a Falling Star

 * One inmate has a orange stripe on his chest instead of white.
 * When Ben and Gwen were in the car, Gwen was not wearing her black stockings.
 * When Ben nearly hits the truck the Ultimatrix symbol is missing from the wheels of his car.
 * When Jennifer was talking to Captain Nemesis in the limo, first her arm was under his arm, but in a scene after, her arm was above his.
 * In one scene, stripe on the chest of Nesmith was on the right side.
 * For some reason, Goop's Anti-Gravity Projector was once more able to pass under the door, the first time being in ...Nor Iron Bars a Cage.
 * When Ben is fighting Carl, Carl's mustache briefly gets skin-colored.
 * When Ben was Goop, he said he accidentally melted the doorknob, but the doorknob was still intact.
 * Gwen says "Remember, keep it quiet". After that she says "That's your idea of quiet?" even though Ben did not actually make any noise other than the sizzing of the doorknob melting.
 * When Swampfire complains about the smell of the operating room the bowl, that Gwen later suggests has blood in it, is empty.
 * Ben leans Gwen against the wall and removes his hand, but then Ben's arm is behind Gwen's back again.

The Eggman Cometh

 * When Natalie Tennyson is cooking in the kitchen, the dish in her hands change size.
 * In one scene, Kevin has six cartridges instead of seven.
 * When Kevin is teasing Ben when he wants to continue their training, when Ben raises his Ultimatrix arm up, the Ultimatrix is overlapping his jacket.
 * When Gwen talks on the phone, one cartridge on Kevin's ammunition belt disappears.
 * In Kevin's Car, Ben moves from the left to the right and then to the middle.
 * In one scene, Kevin is not wearing a seatbelt.
 * When the scientist is talking, Ben's jacket stripes are gone.
 * In the scene where Ben enters the old steel mill, before he becomes Big Chill, the garage-type door behind him is open, but after he becomes Big Chill, the door is closed.

Night of the Living Nightmare

 * When Ben was fighting the Dream Eater, the Ultimatrix's dial was turned.
 * Goop changed directly to Ultimate Spidermonkey without first turning into Spidermonkey.
 * In one scene, the door on Kevin's car is grey instead of green.
 * When Ultimate Kevin is holding Ben by his wrist, Brainstorm's arms are discolored for a split second.
 * In Albedo's nightmare, when we first see the aliens, Cannonbolt is behind Diamondhead, but when we see them from the back, Cannonbolt is in front of Diamondhead.
 * In Albedo's dream, Cannonbolt had one line on his back.

The Beginning of the End

 * When Four Arms sits, his underwear is red.
 * When Clockwork showed the past in The Eggman Cometh, Gwen and her mom were talking backwards, but when Clockwork showed the past this time, Conduit Edwards was not talking.
 * When Goop was cut into half by the Forever Knights, even the Ultimatrix was cut.
 * After Sir George killed Edwards, Winston was lying in a crater. However, when he was hit by the energy blast, there was no crater.
 * When Heatblast lands in the depression he created, the hole is about his waist level However, in the next shot, it is at his knee and in the shot after that, it is almost at his chest.

The Ultimate Enemy: Part 1

 * When the wave turning humans into Esoterica reaches the tennis stadium, all the people should have transformed at once. However, Julie's opponent becomes an Esoterica and after about three seconds, the crowd follows suit.
 * The crowd watching Julie's match also doesn't react or even move their heads at all when they see Ship form around Julie.
 * When Gwen is under the control of Diagon, Humungousaur has lips the color of his skin.
 * When Gwen overpowers Humungousaur, the glow on her hand is missing.

The Ultimate Enemy: Part 2

 * In the scene when Ultimate Way Big fell down, his hands are miscolored.
 * The river Ultimate Way Big fought in covered his feet, but when he reverted to Ben, it had become much shallower.
 * When Ben transformed into Ultimate Wildmutt, he only had three gills instead of four.
 * When Ultimate Wildmutt was attacking the Esoterica, his lips were the same color as his skin.
 * In one scene, after Ben transformed into Ultimate Wildmutt, Kevin's body was not covered in metal.
 * After Ben had gotten up after reverting from Chromastone and Sir George had been turned to dust, Gwen appeared noticeably taller than Ben despite the fact that they are normally around the same height.
 * In one scene, after Vilgax destroyed the Plumber base, Gwen's helmet was gone.
 * In the scene where Ben is in the midst of being tempted by Vilgax into using the power of the Ultimatrix, Ascalon, and Diagon to rid the universe of evil, Julie suddenly is able to help Gwen and Kevin talk him out of it, despite not being present when the conversation started and shouldn't know what's happening.
 * The flashbacks from previous episodes showed scenes that Ben wasn't present in despite said flashbacks supposedly coming from his mind.

Ben 10-Generator Rex: Heroes United

 * When Ben and Rex were on the building, Lodestar's mouth was open when the billboard started to fall.
 * When Rex is trying to remove the Nanites from Rath, Rath has dark green pupils.
 * In one scene, Rath has five fingers.
 * When Rex is first holding Six his glasses are off and his eyes are closed, then when Rex tells Ben it was all his fault Six has his glasses on.
 * When Big Chill was talking to Rex after escaping from Providence the inside of Big Chill's eyes were light green and the outside was dark green, but when he froze Rex's fist the inside of his eyes were dark green and the outside was light green.
 * In one scene, Diamondhead's head has an error.
 * In the flashback:
 * both Echo Echos have different lip colors
 * Big Chill's wings are gone and so is his chest plate
 * Chromastone's mouth is green
 * Upgrade's lines aren't glowing
 * one of Ripjaws's eyes is pink while the other is green
 * Diamondhead's spikes are missing
 * the dashes coming off of Cannonbolt's eyes were green instead of black
 * Wildmutt is missing teeth in the middle, Rath's fur is gone
 * Four Arms' black stripe that connects to his chin is gone and his two golden stripes are also gone
 * Stinkfly's Ultimatrix symbol is on his head.
 * During the flashback, Ben says there is DNA in the Omnitrix even though he is wielding the Ultimatrix (and that the DNA is actually on Primus).
 * When Ben transformed into Upgrade, the Ultimatrix symbol wasn't there at all, but when Upgrade merged with Rex, the Ultimatrix symbol appeared.
 * When Ben reverts from quite a few aliens in this crossover, the sound of the Ultimatrix being activated and then hit down is played.