Pooh's Double Trouble / Eeyore Sleeps on It - S1-E19
Factual error: The letters and symbols on the characters' reflections in the mirror look like their regular counterparts, when they're supposed to be in reverse.
Unicorn Club/Go Gomez! Go! - S1-E2
Continuity mistake: When the cats are entering the race the height of the sign lowers when Waffle walks up.
Continuity mistake: The broken glass on Nathan's face and arms disappears when he is pouring out the rice, but reappears when he is yelling into the PA system.
Continuity mistake: Just after Otis makes the ghost sounds from inside the house, it shows the gang standing together outside the house. Otis is with them outside, which is impossible, as he is inside the house pretending to be the ghost.
Well Bargained and Done - S1-E2
Character mistake: Tybus says he has a lance of 5 mechs. In Battletech, a lance is 4 mechs. While a Clan star does have 5 mechs, Tybus is an Inner Sphere character.
Fiend is Like Friend Without the 'R' - S1-E4
Continuity mistake: Mandy hits a baseball with one of Grim's bones, yet when we see Grim, there are none of his bones missing from his body.
The Secret Of The Juice - S1-E10
Continuity mistake: When Tummi goes looking for Zummi, Gruffi and Cubbi, he arrives right outside the barrel room. When first seen, the barrel room door is smooth, but in the next close-up the door suddenly has an iron grill window in its surface.
Continuity mistake: In the scene where Thugnificent is giving Riley is new chain and holds a speech, we can see that Riley's chain is as long as Thugnificent's. However, when he actually hands it over to Riley and when Riley does wear it, the chain is considerably shorter to compensate for Riley's length. (00:10:10)
Half-Baked - S2-E2
Continuity mistake: There are three boxes of cupcakes stacked on the coffee table. However when Trixie picks them up, as the shot changes there are now five boxes of cupcakes. (00:12:10)
Happy Birthday, Kevin (or Happy Birthday, Douchebag) - S1-E12
Continuity mistake: After Carlos sees the snake on the pole he leaps off the roof onto the pole. When he jumps you can see it's quite a distance from the roof. After catching the snake he is holding onto the pole and asks to be helped back onto the roof. The other characters just put their hands out and pull him up. There was no way with the distance between the pole and the roof they could have come close to reaching him the way they did.
Continuity mistake: In the scene where Mr. H. Makes Bloo wash his hands, Mr. H takes off his gloves and washes his hands then dries them. Notice that as soon as he takes his hands out from underneath the towel his gloves are back on.
Continuity mistake: Whenever Banner changes into Hulk his clothes rips, only his pants stays on. But when Hulk changes back to Banner, he suddenly has all his clothes on, no rips or tears at all.
Sins of the Fathers Chapter 1: Doctor Strange - S3-E1
Revealing mistake: When Mary Jane and the other servants of Baron Mordo are flying through the city, they literally disappear into thin air. Probably a problem with rendering the 2D animation within the 3D animation. (00:01:00)
The Whirly Dirly Conspiracy - S3-E5
Continuity mistake: When Beth glues the horse hoof on, the bottom is facing up. In the next shot it facing to the side. And then the leg changes shape in different shots.
Continuity mistake: Before boarding her helicopter, Jade kisses Race as her head is turned towards her right shoulder. The next shot her head is turned towards her left shoulder.
Continuity mistake: When Kimiko says "Will you two please stop abusing the English language!", Raimundo's eyes are blue.
Origin of Iron Man: Part 1 - S1-E11
Character mistake: When young Tony Stark is telling his father that their helicopter's anti-flak chip didn't kick in, he acknowledges that it was his fault by saying he blew it. When his father corrects him and says "No Tony, we blew it. Stark and Son," Tony defensively says "The anti-flak chip failed, it's not my fault," completely contradicting what he said seconds earlier. (00:14:00)
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)
Continuity mistake: When Lin lifts the rocks around the house in the final scene, there are eleven of them. But in the last shot, there are only eight rocks.
Continuity mistake: When the gang arrives at the fashion show, they park the Mystery Machine at the end of the walk way. But when the head of the fashion show is shown, the Mystery Machine has vanished. (00:03:05)