List of goofs/Season 1

Tourist Trapped

 * The "ENTER!" sign in Stan's arms points to the left, and there are two signs behind it pointing to the right. When they are handed to Dipper, the "ENTER!" sign points to the right and the two signs behind it point to the left.
 * While Dipper was reading from Journal 3, he read "studying" even though the book said "researching."
 * The book 3 that Dipper discovers has a hand symbol on the book cover that alternates between five and six fingers in several scenes.
 * During the cart chase right after the gnomes miss the first attack Dipper's hat is gone and reappears after a gnome lands on the cart.
 * After Dipper and Mabel crash the Mystery Cart, its position moves several times throughout the scene.
 * When Dipper and Mabel are being chased, a rear shot of the back of the Mystery Cart shows that Dipper's hat is missing despite it being present in the preceding and following shots.
 * The leaf blower sucked Mabel's lips, but the "smooch mark" was on her cheek.
 * When you see the triangle stained window from the inside it is centered with a double ring, but from the outside it has a single ring.
 * When Mabel is responding to Jeff's proposal, Jeff's beard is red instead of brown.
 * When Wendy pulls up in the Mystery Cart, there are four flaps across the top. But when Dipper goes to save Mabel, there are only three.
 * When Dipper first gets the Mystery Cart the flag in the back is missing.
 * Dipper throws a shovel at the gnomes and is shown that it was left at the gnome hideout but later reappears when Dipper grabs it to throw it at the giant gnome monster.
 * When Dipper throws the shovel at the gnomes, Dipper and Mabel are a few feet apart, but in the next camera angle they're holding each other.
 * Dipper says that Norman never blinks but Jeff does in fact blink.
 * When it shows the map of Oregon, Corvallis is spelled Corvalis.

The Legend of the Gobblewonker

 * When Mabel says "blah" after coughing on syrup, her mouth doesn't move.
 * Grunkle Stan's license plate reads "STNLYMBL" which is 8 characters long, but in the state of Oregon, the max number of characters allowed on a license plate is 6.
 * When Soos lost his shirt, it reappeared during one of the fishing pictures and disappeared again after the pictures.
 * When Old Man McGucket says "Aw, banjo polish!" when he was leaving the screen, his mouth didn't move.
 * When Soos grabs Dipper by the top of the life-jacket when they are running away from the Gobblewonker, one shot shows Dipper wearing the life jacket, and it is raised up so you can see his stomach. However, when the shot pans out, the shirt that he is wearing under his life jacket covers up his stomach.
 * Dipper's fishing hat lost the last two letters during the pictures, but later all the letters are back.
 * During Mabel's daydream with the hamster ball, Xyler had blue framed sunglasses and Craz had pink framed sunglasses. After Mabel talks to them both had pink frames.
 * In the pictures of Stan, Dipper, Mabel, and Soos the letters on Dipper's hat are all blue and the letters on Mabel's hat are all pink.
 * In the first picture Dipper took, Mabel's hat's name colors are the same, plus, before Dipper took the picture you can see Soos' arm, but in the picture you don't.
 * When Soos is throwing the cameras at the Gobblewonker, some cameras randomly appear in his hand.
 * When Dipper meets up with Stan he had his hat on, but when Mabel and Dipper put on his fishing hats, Dipper's hat disappears.
 * When Soos was throwing cameras at the Gobblewonker, he had about 9 or 10. But they only had 8 left.
 * When the trio first enters the cave, Soos lets go of the beaver and it lands onto the floor, but in the next scene, it disappears.
 * When the boat drives through the glass pane, the robot Gobblewonker disappears until Soos, Dipper, and Mabel are about to crash in the cave.
 * The credits used Jason Ritter's middle name instead of his last. He is listed as Jason Morgan.
 * As Dipper says "Change of plans," a gap opens in the line that makes up Mabel's hair, only to vanish a second or two later.

Headhunters

 * Wax Larry King is first shown to be the same height as Wax Sherlock Holmes, but in the next scene he is much shorter.
 * Mabel's drawings of her sculpture ideas had color, but she was using a regular pencil.
 * When Deputy Durland and Sheriff Blubs raid Toby Determined's office, Deputy Durland says 'Derp' without moving his mouth.
 * Shandra Jimenez is not at the re-opening of the Wax Museum, but she is there when Mabel calls on her for questions.
 * When Grunkle Stan left to use the bathroom, the lights were on, but when he came back, the lights were off. However, the wax figures may have done this so they didn't melt or weren't caught.
 * When Mabel leaned forwards to say, "Even us!" the button on her disposable camera disappeared.
 * The footprints left holes in the shag carpet pushed down into the carpet. If the shoe had a hole in it, the carpet fabric would push up into the shoe.
 * After the flashback of Manly Dan punching down the pole, the jar of eyeballs on the counter disappears.
 * Grunkle Stan's eyes are white when he says "Thank you all for coming".
 * Some of the footprints that are supposed to have holes in them don't have holes.
 * When Blubs and Durland checked the axe for fingerprints, they would have found Soos, Dipper, and Mabel's prints because they each touched it earlier.
 * When the security footage of Toby is shown the first time it starts at 10:00 and the seconds are at 1. But the second time it is shown, the seconds are back at 0 and the clock still says 10:00.
 * All of the wax figures have the hole in their shoe on the right. The ones on the carpet show a hole on the left.
 * The wax figures say they come alive during a waxing moon, but the moon shown during the fight between Dipper and Wax Sherlock Holmes is waning.
 * Toby Determined had a picture of wax Grunkle Stan's head, despite it being missing at the time.
 * When Grunkle Stan leaves to use the bathroom, Wax Stan has a stand. Yet, when he is on the ground, the stand is missing.
 * Manly Dan's name is misspelled as "Manley Dan" in Dipper's list of suspects.
 * Wax Robin Hood's bow switches from having an arrow to nothing.
 * In the scene where Mabel says, "Are you saying you could outwit Duck-tective?", before she says her line, her eyebrows and eyelashes are missing.
 * In the flashback when Dipper explains why Toby Determined was the murderer, Toby's left shoe had the hole inside. But when they show the footprints, the hole was in the right shoe and earlier it was in the left shoe when they looked on the carpet.
 * In the flashback where Wax Sherlock Holmes decapitates Wax Stan, he appears to be sitting down because his legs are bent. When Wax Stan falls, he is standing up again..
 * In the flashback where wax Sherlock Holmes decapitates wax Stan and he looks at the head, the design on the hat is missing the little triangle.
 * Despite being British, Wax Sherlock Holmes uses the word 'pants' when he says "Outsmarted by a child in short pants? Noooo!"
 * When Stan regains Wax Stan's head after the battle, the color of the band on the back of his fez changes color for a few frames, from yellow to red, and then it goes back to normal.

The Hand That Rocks the Mabel

 * When Gideon Gleeful touches his amulet as he forces the crowd to stand, it doesn't glow like it does in all the other scenes of the episode when he touches it. This may have been to keep the amulet's powers a secret until later in the episode.
 * Before Mabel shows her makeover to Dipper, Dipper's book has a Journal 2 instead of a 3. The book labeled 2 belongs to Gideon Gleeful, making this impossible.
 * When Mabel complains that Dipper never does girly stuff with her, we see the book he was reading resting on the arm of the chair, but when Soos shows up with the hot dogs, it disappears.
 * In the close-up when Mabel is playing a video game with Dipper, the collar on her sweater has stripes. In all the other shots, it did not.
 * When Dipper and Mabel are playing with Soos, Mabel is wearing a sea-foam green-colored headband, but when Dipper hears the phone ring, her headband changes to red, then back to sea-foam green.
 * When Mabel blinks, the "bezazzles" on her right eye fall off, but they later return.
 * When Mabel coughs up "bezazzles" on Gideon Gleeful's jacket, they stick to it. But in the next shot, the jewels are gone.
 * While Mabel is on the boat with Gideon, she is wearing a headband, but when she gets back home, she is wearing a hair clip.
 * When Grunkle Stan runs away with the clown picture, one of his legs are missing.
 * After Dipper and Mabel are sitting on the couch, when Grunkle Stan talks to them, the umbrella on Mabel's sweater is gone. In the next frame, you can see part of the umbrella.
 * During the end credits Soos, Mabel and Dipper are using a flashlight, but it did not cast a shadow.
 * Also during the end credits, when Soos spins to the side with no jewels on it, the wall still has the disco ball effect.
 * Again, during the end credits, the light reflections rotate in the opposite direction Soos is spinning.
 * Once again during the ends credits, you can clearly see the colored lights repeatedly cover Mabel's face but not Dipper's.
 * Again in the end credits, Mabel's 'bezazzling' gun is not shown.
 * Yet again in the end credits, the lights on the wall travel much slower than Soos is rotating.
 * When Gideon Gleeful and Mabel are on the factory together, the factory switches between having an elevated roof in the background to have no elevated roof at all.
 * When Gideon Gleeful and Mabel are on their date, we never see Mabel's glass filled with water and yet when the waiter leaves, it is full of water.
 * Also, a few seconds before the waiter leaves, you can see the water full, but it has no bubbles.
 * Before we see Gideon and Mabel close-up on the boat, you can't see her headband.
 * When Mabel comes back from Gideon's dressing room with her makeover done, Mabel doesn't have any eyebrows in that scene.
 * At one point, on the outside of the Mystery Shack the sign says "World Papov" instead of "World Famous."
 * At the 15:28 time frame, Mabel's headband is bluish-green in color. However at 15:33, it's pink.
 * In a frame when Mabel is wondering how Gideon Gleeful found out her name all but one of her teeth are missing.
 * When Buddy enters Gideon's room, the photo Gideon burns is not shown on the door.

The Inconveniencing

 * When Dipper is trying to climb over the fence, Lee is on the same side as everyone else, the same side as Dusk2Dawn, but before he pushes Dipper off, he seems to be climbing from the outermost side of the fence, as if he was going in.
 * If the store was actually condemned, it is unlikely there would still be food there. Though, it's possible that no one bothered to clear it out.
 * In the scene when they first arrive Dipper goes to get the newspaper, When the newspaper is on the stand,the title reads USA WEEK but when Dipper rubs off the dust, the title now says NEWZ.
 * If the store had been closed for years with the power off, then the ice they got from the freezer would have just been bags of water. Though the brain monster could have been preserving it.
 * When the three teens' reflections are shown in the window as normal, Tambry is smiling instead of just staring.
 * In the same scene, Tambry's leggings disappear.
 * In the end credits, instead of listing Dipper's voice actor as Jason Ritter, he's listed as Jason Morgan.
 * Ma and Pa collapse from heart attacks by the window near the front door, but their bodies are chalked near the end of the store.S1e5 thompson car 02.png
 * In the chalk outline, Ma's arms are sprawled out but when they show her collapsed in the flashback her arms are on her chest.
 * Robbie was the only teen besides Wendy that did not get turned into anything and he vanished when Wendy and Dipper were lifted onto the ceiling, and appears again when the ghosts let them go.
 * When the two were lifted onto the ceiling, the hot dog machine was not turning the hot dogs.
 * Tambry is not spotted in the minivan when Thompson drives the "gang" to Dusk 2 Dawn, even when there was a seat next to Mabel and Dipper.
 * When Wendy is telling everyone about how Dipper saved them, the mud on her boots is at the top, but when it shows her again the mud is on the bottom of her boots. In the same scene, Dipper has a peach-colored nose instead of a red one.
 * Thompson parks the minivan outside the fence when they arrive, but when Pa (speaking through Mabel) opens the doors, the minivan is inside the fence. When they get out, the minivan is outside the fence again.
 * In the scene when Dipper is opening the vent to get inside, Tambry's leggings briefly vanish again.
 * The open and closed sign changes from open to closed many times in different scenes.
 * When Dipper does the Lamby Lamby Dance, Ma's name tag is on her shirt, but when he finishes, it is gone.
 * When Dipper is seen with his clipboard from far away, his pen is in his left hand. Shortly after, it switches to his right, and then back to his left in the next shot.
 * When Mabel and Dipper are in the van and Mabel is saying "This is going to blow someone's mind!", the pine tree on Dipper's hat is outlined in black.
 * When Thompson is first seen playing Dancy Pants Revolution, the arrow that points left is white. But when he is trapped in the game, it is pink.
 * Robbie's eyes are translucent for a few frames.
 * Mabel said that the Lamby Dance mentioned grazing, but in the actual song, grazing wasn't mentioned. Though Dipper could have just sung part of the song.
 * Early in the episode, the door to the roof, when viewed from outside, is shown opposite to the ladder inside.

Dipper vs. Manliness

 * Right before Mabel asks Stan for pancakes she has a spoon stuck on her nose but a second later it is gone
 * When Sheriff Blubs is eating pancakes, he is almost done, but when it shows the number of pancakes, and then cuts back to Sheriff Blubs, it starts from the top again.
 * When Dipper is first seen walking down the street, the fire hydrant was fine and Sheriff Blubs and Deputy Durland weren't anywhere around it.
 * Dipper throws down the beef jerky on the ground and Chutzpar eats it. It cuts then cuts to a closeup of Dipper and then back to the previous shot, but the jerky is now missing.
 * When the animals are running away in the forest Dipper's hat disappears then appears in the next scene.
 * Mabel couldn't have seen Dipper's chest hair because his shirt would have covered it.
 * When Soos runs out the door, the door moves a little and then stops, but the style of the door and its position could not let it do that.
 * When Mabel gets an idea Soos's shirt is pink but when Mabel gets up his shirt is back to normal.
 * In the hot tub scene, when Dipper thanks the Manotaurs for teaching him to be a man, there are two manotaurs in the background but they disappear when one of the manotaurs tells him of his last task.
 * When Mabel and Stan were weirded out when Dipper said about the Manliness tester, the manliness tester said Manliess

Double Dipper

 * When Stan answers Soos' question about whose birthday it is, his bow-tie disappears.
 * Dipper says the first thing on his list is to talk with Wendy, but later it shows "smile" instead of talking.
 * Dipper says he has to follow steps 1-11, even though there are 20 steps.
 * The last two items on the list say "monstermon" instead of "monstermen".
 * Some of the people from inside of the party reappear in the line by the ticket stand.
 * In the line when kids start waving around their arms to pay in cash to Wendy, one of kids near the front doesn't. As consequence, he has missing arms.
 * When Pacifica Northwest comes out of the bathroom, her colors are faded.
 * In several of the shots, the writing on Dipper's Plan is gone.
 * When Dipper and Wendy cheer, Dipper picks up his soda on the floor but he did not bring a soda in the hallway in the first place. The cup that he picked up was shown earlier to be spilled, yet when the clones confronted Dipper, he dropped the cup and soda spills out.
 * When Dipper is talking to Wendy outside the bathroom, Wendy says "that guy" would be the leader of the island. They cut to a shot of "that guy" and Pacifica is near him on the dance floor. Moments later, she emerges from the bathroom.
 * Dipper sets off the fire sprinklers with smoke from a party popper. However, fire sprinklers are activated by heat, not smoke.
 * The red spreader stick in the crackers and cheese snack is not visible in the package, but it appears in Dipper's hand later.
 * When Mabel was dancing, there was a chair next to Candy Chiu but in the next scene, when she sat down to drink water, the chair disappeared.
 * When Mabel sprays her silly string at Dipper in the copier room, the string comes out of the side instead of the nozzle.
 * When Dipper drops his spray deodorant, the appearance of the can changes.
 * When Wendy tells Dipper she and Robbie are going to go sit on the couch, his bow tie is missing, and later it reappears.
 * The part where Dipper is reaching for his body spray, there is no blue jar on the case. Later, a blue can appears.
 * When Paper Jam Dipper emerges from the paper, part of his shoe is missing in a frame.
 * Soos said Robbie's dirt bike was being stolen, though it was actually a regular bike.
 * When the clones confront Dipper while Wendy was in the bathroom, the copies of "Wendy Plan B" are the same as the first plan.
 * Right before Dipper and Tyrone say "We blew it man," Tyrone's hand is a frame early for several frames, causing his hand to be severed.
 * When Dipper spills soda on the copied arm, it only covers half the arm but in the next scene all of it is covered.
 * The "Wendy Mix" starts playing before Clone #10 puts it in.
 * When Mabel was singing, one of the people cheering her on did not have an ending to their left sleeve and it covered his whole hand.
 * After the battle for the party crown had begun and Mabel is dancing, she is missing her braces.
 * Robbie played his electric guitar despite the fact it was not plugged in to an amplifier.
 * When Wendy leaves Dipper to man the table by himself and she starts dancing inside, for a few frames her left shoulder is filled red.
 * When Grenda says, "Hold me, Candy," Mabel has two right eyebrows. As she turns to face Pacifica Northwest, her upper eyebrow comes down and vanishes into the lower one.
 * When Dipper says to Wendy, "in exactly 42 seconds", he is wearing a wrist watch, but throughout the episode, he is not wearing the wrist watch.
 * When Dipper was telling Soos that someone stole Robbie's dirt bike, his colors are faded like the clones.
 * Tambry's purple hair extension is on the wrong side through most of the episode.

Irrational Treasure

 * When Grunkle Stan says "I will break you, Little Man!" to Toby Determined, the line between his eyes (part of his glasses) disappears.
 * When Sheriff Blubs is speaking into the microphone saying that the speech will begin, the microphone is there. When it zooms in a little bit, it is gone. But in the next scene where Pacifica is speaking, the microphone reappears.
 * When the statue of Nathaniel Northwest is first seen, it is in front of a church. However, when Dipper is reading 3, there is a group of trees behind the statue.
 * Pacifica pulls the pen and paper out of nowhere when she hands it to Stan.
 * The pen in Grunkle Stan's mouth disappears after Pacifica reads the note he wrote.
 * When the twins exit the museum, the right hand door is open, however when the officers leave, the other door is the only one open.
 * When Dipper is going through the slides in the library, one is entitled "Numerology", but contains astrological symbols.
 * Mabel's mouth doesn't move when she laughs when Dipper says to look out for "booby traps".
 * In the video, they cover the picture of Quentin Trembley with a picture of William Henry Harrison. Above Trembley's picture it says "8th President" even though he succeeded the 8th president. The picture shows above that he is the 9th president when the video is about to end.
 * In the top secret document that reveals Quentin Trembley as the founder of Gravity Falls, in the second paragraph, the "Falls" in "Gravity Falls" isn't capitalized.
 * In the document, it says there are 6 babies, but on-screen, there are only 4.
 * While watching the video, Mabel's eyebrows raise in surprise at the revelation that Quentin Trembley was once president. Her expression then shifts to confusion and her left eyebrow curves down onto her eye, but the surprised eyebrow is still on her face, giving her three eyebrows.
 * When the twins and Trembley climb the ladder to the top of the train, they are in the rear car. However, when they emerge on the top of the train, there are more train cars behind them.
 * While Dipper and Mabel read about the conspiracy in front of the statue, the bottom of Dipper's shoes change from white to black.
 * When Quentin Trembley is inside the block of peanut brittle, his expression changes throughout different scenes.
 * When Dipper is running towards Pacifica to tell her about Quentin Trembley, Mabel's headband disappears.
 * When Dipper removes the document, the red spots on Mabel's cheeks are not present.
 * Gompers at the wedding ceremony is drawn with a short right horn instead of a short left horn.

The Time Traveler's Pig

 * In the flashback of the events of "The Legend of the Gobblewonker," the Soldier Kid and the Free Pizza Guy are seen, but they did not appear in that episode.
 * Blendin Blandin's watch switches hands when he is confronted by Mabel and Dipper.
 * Dipper's question mark corn dog disappears when Robbie shows up.
 * The caramel apple Mabel feeds Waddles disappears after she drops it.
 * The flash of light caused by Blendin's time machine in the credits during the events of "Headhunters," is not featured in the actual episode.
 * In the second to last reality, Mabel looked at the pictures of her and Waddles. However since she lost Waddles in a different reality she could have never have been able to take the pictures.
 * When Blendin's "position was compromised" after he failed to hide, his watch switched from his left hand to his right hand.
 * After Mabel hands Blendin tickets to the fair and he leaves, Mabel turns to the side, and her flower has vanished.
 * When Mabel loses her flower, it is on the other side on her head.
 * When Waddles is dressed as a doctor and follows Mabel to Blendin, his clothes disappear.
 * When Blendin walks to the barrel ride, the time machine is not on his belt. When the camera zooms in, it is.
 * The first time Dipper plays the ball toss, Robbie comes 10 or 20 seconds after Wendy gets a black eye, but many times while Dipper "do-overs" with the time machine Robbie comes earlier or right away sometimes even coming at a different direction.
 * In one of the scenes where Dipper and Mabel are talking to Blendin, Mabel's eyebrows disappear.
 * When Robbie talks to Wendy in Dipper's final do-over, there is a frame in which his teeth are skin-color as opposed to white.
 * When Dundgren is talking to Blendin, there is a frame in which his pupil is colored light green instead of black.
 * When Dipper and Mabel travel back in time to the episode "Headhunters", you see the pizza shirt guy wearing a green shirt, but in the actual episode, his shirt is red.
 * When Mabel is riding the Ferris wheel with Waddles the ticket booth in front of the Ferris wheel is facing to the right. In all the other "do-overs," it is facing toward the front.
 * When Wendy first sees the stuffed animals, they are seated on a board, but when they walk up, and the rest of the time, they appear to be dangling.
 * When Dipper goes back in time to get Waddles back for Mabel, she remembers everything that happened even though she did not travel back in time with him.
 * In the final reality, Blendin confronts Mabel and Dipper, but he didn't go with them and wouldn't remember it.
 * When Grunkle Stan laughs at Robbie, his finger leaves the border of the dunk tank.
 * When Mabel sat on the Test Your Strength game, the marker did not move when she got off, but it should have gone to 0 since it is impossible for Mabel to weigh 0 pounds.
 * Mabel's eyes are off-model, in one scene her eyes are parted in the middle.
 * When Soos tells Blendin to take of his belt because of "tools", the only thing it holds is his time machine.
 * When Mabel was playing with "Doctor Waddles", his nose color briefly changes.
 * When Dipper and Mabel high-five each other in the Mystery Shack, Mabel is seen without braces.
 * When the twins travel to when it was opening day in The Legend of the Gobblewonker, the sign says "Fishing Season," however in the actual episode it says "Fishing Season. Opening Day"
 * Fertilia's baby sports an adhesive bandage on his cheek, but they were not invented until the early 1900s.
 * When the Unnamed hillbilly throws balls at the dunk tank, his right hand is shown with no half-finger missing.

Fight Fighters

 * When Wendy and Robbie were playing the game they were moving the joy stick and pressing the buttons, but in the next scene, if you look closely, there is nothing happening in the game.
 * When Rumble McSkirmish came out of the video game he slammed his fist down causing cracks in the ground, but in the next shot, they were gone.
 * When Mabel wins the crackers in the card game, nobody else had any. However, in the next scene, Dipper and Grunkle Stan both have more crackers.
 * When Robbie pushes Dipper down and then walks away, the trash cans and Dipper's hat disappear. They then reappear when Grunkle Stan comes out.
 * Robbie says he plays lead guitar, but his guitar has only 4 strings, which is a bass guitar.
 * Also when Robbie walks away, his cellphone and amp are gone.
 * When Robbie was on the Water Tower, Rumble looked up at him to see where he was, but when Dipper was on top of a tree, Rumble said he didn't have "a looking-up animation", even though he looked up at Robbie a few scenes back.
 * Rumble said that he couldn't stay still, but when Mabel meets him, she hands him the paper with words for him to say, and he stays perfectly still and constantly stays still when talking to Dipper.
 * When Dipper is following the instructions "to unleash ultimate power", he only presses the punch button twice.
 * When Grunkle Stan falls backwards away from the TV, he falls on the floor. However, the wall is supposed to be closer to the dinosaur skull than it was in the aforementioned scene.
 * When Dipper is at the arcade and looks at the posters of Robbie, his watch disappears, but then later reappears.
 * When Rumble is on the floor, his eye patch keeps changing which eye it covers.
 * When Dipper was fighting Rumble, he shot a blue orb. In the scene right after, it's red.
 * In some scenes Robbie has five fingers while in others he has four.
 * When Rumble and Robbie are fighting, a poster for Robbie's band appears on the tree behind Dipper and Rumble, after Rumble wins.
 * As Grunkle Stan complains that, "[Mabel] doesn't even know what [they're] playing", Mabel's mouth closes without any animation.
 * As Dipper and Rumble are walking through the streets, a barber shop appears in the background during the start of the scene. As Rumble acquires a pipe, a poultry shop is visible behind him. When the camera zooms out, the barber shop from the scene's start appears in place of the poultry shop.
 * When the Fight Fighters game turns off before Rumble comes to life, Dipper's hat turns solid blue.
 * While Grunkle Stan is aligning the T.V. antennae, during the skydiving scene, his mouth animation is shown in two places simultaneously for one frame.

Little Dipper

 * The Gummy Koala candy bag had a net weight of 5.29, but later, it reads that the net weight is 6.29.
 * When Gideon grabs the contract, the front of it is faced towards Stan. In the next scene, the paper switches to the other side without Gideon moving his hand.
 * When Grunkle Stan knocks the jar of termites out of Gideon's hands, it falls on the porch. When Gideon runs away, it is in the doorway.
 * Dipper grows the pawn while it is on the chess board, but later, it is shown in the background, out-of-place.
 * When Dipper and Mabel are fighting over the flashlight, the caterpillar ran over a couple of cars but when Dipper and Mabel drop the flashlight the cars are gone.
 * The Mystery Shack model is on the left side of Gideon's desk in the beginning. Later, Gideon closes his book and it is on the right side of his desk.
 * The photo of Gideon on his ID card shows him with only four fingers per hand.
 * When Mabel charges into her room, the closet door is open. But when she suspects a wizard made Dipper taller, she looks in the closet and has to open the door even though it was open and not tampered with when she arrived.
 * When Dipper and Mabel tickle Gideon, the pine tree on Dipper's hat is missing.
 * When Gideon puts the jar with Dipper, Mabel and Soos into his breast pocket, the jar disappears.
 * When Mabel was in the bag Gideon put her in gummy koalas it showed Mabel without a headband. Later it came out in the bag.
 * When Gideon was playing with the flashlight before he shrunk the twins, it's hard to notice but it was making the grow sound effect.
 * When Gideon is running away from the termites, he leaves the jar they were in at the shack. However, when he shrunk Dipper and Mabel, he has the jar again.
 * Dipper and Mabel are not visible in the jar when he turns to face his dad.
 * During the flashlight duel, Mabel and Dipper do not flick the crystal, but the beams change.
 * When Mabel and Dipper are playing chess, Mabel moves a black pawn and Dipper says it is not her color (implying her color is white). He then uses a white pawn to take out the black king.
 * When Gideon is on the phone with Stan, he has a brush in his hand. When the scene comes back to Gideon, his brush is gone.
 * When Soos takes off his cap, his hair is brown, but in the mirror his hair is gray.
 * Before Stan places his fez on the dresser, the fez symbol is not reversed in the reflection. When Soos wears it, it is. This may be a clue rather than a goof, as it has also happened in Boss Mabel.
 * Also in the mirror, Stan's suit reflects normally, but his tie does not.

Summerween

 * When Stan pulls up to the Summerween Superstore, he parks in front of a handicap parking sign. However, the sign is facing away from the parking spot instead of toward it.
 * After Mabel finishes talking about previous Halloween costumes, Dipper eats a candy, and while he is choking, there is a short flash of which Dipper's back part of his hat is not blue; it blends in with the wall behind him.
 * Right after Dipper and Mabel come back from the Summerween Superstore, they are seen on the floor in front of Soos, with many items such as scissors, a pencil, and glue, but when Soos is telling them to be careful, everything disappears. During the time when Soos is telling Dipper and Mabel about the Summerween Trickster, everything reappears.
 * Dipper's watch is nowhere to be seen when he looks at Tambry's party flyer, but when Dipper looks up, his watch reappears.
 * When Mabel opens the door for the Summerween Trickster, Dipper was standing near. However the door never hit Dipper, nor was he there after, but it appears later on.
 * In Mabel and Dipper's music number for Halloween at the biker's house, the treat bag disappears. When he gives them the candy after it ended, it reappears in their hands.
 * During a few frames, the strawberry on Mabel's costume leaned in a different direction.
 * When Soos' truck was recklessly driving through town, it had a blanket draped on the back end of the car. After the car crashed into the store, it disappears.
 * When Soos hits the Summerween Trickster with his truck, Gorney can not be seen. But in the store when Soos is eating out of the Summerween Trickster, Gorney comes out.
 * In the Summerween Superstore, the skulls in the bowls are in different areas from when they first get there and when Soos crashes his truck into the store.
 * Candy says she took a picture of the Summerween Trickster, but she never pulls her phone out when she first met him.
 * Dipper's watch says 6:00 after they meet the trickster, and it is dark. However, that part of Oregon on June 22 would not have a sunset until about 8:50 pm
 * Waddles has a light brown/tan spot on his left eye rather than his right eye.
 * The Summerween Trickster's eyes are peppermints, but after Soos was eating him and he was screaming in pain and fell on the ground his eyes are just yellow dots.
 * When we first see the Trickster's teeth the are white. But they become candy corn after he reveals that he is made of candy.
 * When Dipper is shocked to see Wendy with Robbie, he drops some candy from the bowl on the ground. When Wendy comes into the Mystery Shack with Robbie to get her jacket, no candy is seen on the floor.
 * In the promo for this episode, the Summerween Trickster is bright purple, but in the actual episode, he is dark purple.
 * When the Summerween Trickster is talking about "every discarded bar of chocolate with that white, powdery stuff" he's explaining it with both hands, even though he only had one free hand.
 * The Summerween Trickster said Dipper, Mabel, Candy, and Grenda had until the last jack-o-melon goes out to get 500 pieces of candy. Yet when the Summerween Trickster came to get his candy, Stan's jack-o-melon was still lit.
 * When the Summerween Trickster first goes into the store for the kids, he tears the door off of Soos's car. When it shows the kids running around behind the Trickster, the car still has the door.
 * Dipper's watch disappears when he first opens the door to the Summerween Trickster then re-appears when Dipper closes the door.S1e12 trick or treating.png
 * Waddles's light brown/tan spot has been replaced with pink spots instead of light brown/tan spots, when he's eating the candy in a bowl.
 * This picture shows many errors in the episode; Gorney is shown in the top left, Waddles in the middle, and Candy and Grenda near the side.
 * When the kids are looking up at the roof of the Mystery Shack after the Summerween Trickster is gone, They are standing in a line with Grenda closest to the left of the scene, then Candy, then Dipper, then Mabel. When the scene moves in closer to them, Dipper and Mabel are farther apart and Grenda is standing behind them.
 * When Dipper was wearing his Peanut Butter costume, his birthmark isn't visible throughout the entire episode.

Boss Mabel

 * When Gompers neighs when a tourist bus pulls up to the Mystery Shack, his mouth does not move.
 * At the end of the episode, when Dipper put his cap again his arranged hair changes, but in the next scene when he is counting money his hair is arranged again.
 * When Soos is in the Mystery Shack, trying to talk to someone, his Questiony the Question Mark costume is reversed.
 * When Mabel gets something from the vending machine, the bag drops off without her pressing the button. She presses the place where she inserted the money instead.
 * When Mabel is holding the Questiony the Question Mark costume, it is normal. When it shows the costume from the other side, it still looks normal, though it should be reversed.
 * When Dipper took out his fake wolf teeth his hand is up, but in the next scene his hand is down.
 * After Dipper grabs the mace and leaps out the window the window is left open. But in the closeup shot of Wendy, the window is closed.
 * When Dipper is counting the money at the end of the episode, Mabel does not have Stan's hat on. But when Stan comes in and talks to them, she does.
 * When Mabel first enters the gift shop with Soos, Dipper and Wendy, the jar has a red line on it. Later, after Dipper leaves, Mabel draws the red line and claims that they will fill the jar with "one hundred billion dollars".
 * When Mabel is yelling at Soos and Wendy, Wendy's legs are cut off.
 * When Tambry is drinking a can of Pitt cola the scene goes to Mabel then when it goes back her the can is gone.
 * When Mabel stands in front of the mirror wearing Stan's hat, the fez symbol is not reversed in the mirror.

Bottomless Pit!

 * Stan's tax forms say 2012. However, they should say the previous year, not the current year.
 * When Sheriff Blubs is telling Stan that there is no Doctor Medicine in Gravity Falls, Stan’s tattoo is replaced with back hair, but his tattoo returns moments after.
 * When the bouncer is talking to Dipper, his tattoos are black in the front and back. When the camera goes to the back, the tattoos are colorful. When it goes back to the front, they are all black.
 * When the bouncer talks to the people from the bar, his belt is way up. When he is chasing Dipper, his belt is in a normal place.
 * Despite the pit being a wormhole, and spitting them out after no time passes, none of the things they throw into it are spat out. Also, when Stan falls in at the end, he didn't come up right away. Again, no time should have passed. The Bottomless Pit seems to spit things out a few minutes after they fall in, rather than right away, as the storm has passed when everyone comes out.
 * The image at the end of the theme song that shows up for a frame still has Stan's old fez design.
 * When Soos wakes up after hitting himself in his eye, his black eye disappears.
 * Dipper puts the screw behind himself. But when he says "Soos, are you out of your..." the screw disappears.
 * When Dipper asks where his spaghetti is, the spaghetti plate has a fork. But when Grunkle Stan spins around, the fork is gone.
 * When Grunkle Stan tries to do a card trick, the Ace of Spades is red instead of black.
 * When Soos wins the pinball game, it somehow knew his name without Soos typing anything in.
 * If the box and shoes were thrown into the pit first, Dipper, Mabel, Soos and Stan shouldn't have caught up with them. They should have always stayed ahead of them.
 * When Stan is asleep, his book is on his stomach. When he is awoken, it has disappeared.
 * When the Tumbleweed Terror skull sucks Mabel and Dipper, Dipper's birthmark strangely is not visible.

The Deep End

 * Soos doesn't have his towel when Grunkle Stan was talking about the perfect lawn chair.
 * Also, when Stan starts talking about the chair, another chair is behind Soos. It then disappears, never to reappear again.
 * When the ship found Mermando, there is nothing behind Earl. But in the next scene, a mountain appears behind him.
 * One water balloon fired off the screen was blue. However when it hit the cooler, the balloon was red.
 * In the shot where Mr. Poolcheck is telling everyone that the Pool's closing, Gideon can be seen relaxing on a lawn chair that doesn't have a tree hanging over it.
 * At some points in the episode, Mermando's mustache hairs move place on his face, and the number of them change from three to four quite often as well.
 * Grunkle Stan's watch reads the same time upon entry and exit of the pool jail, despite being in there for two hours.
 * Every time Dipper gave Mermando reverse CPR, the bottle refilled with water, even when it was empty before.
 * Mermando's gills on his head are almost permanently out of water.
 * When Mermando's bottles for Mabel jump out of the water, the word "Mabel" turns to "Lebam" which is Mabel backwards. And then turns back to Mabel.

Carpet Diem

 * Mabel's eyebrows are gone until the scene of her brushing her hair with her hand.
 * When Dipper realizes that Mabel is having a sleepover, you can see that there are sleeping bags for Candy and Grenda already in the room. When they enter the room, they are holding sleeping bags.
 * In some scenes, Dipper (in Mabel's body) and Mabel (in his body) their eyelashes are missing.
 * For a split second, when Dipper and Mabel are walking through the room, Mabel's blush pink spots gain black lines.
 * Before Dipper reads "Experiment 78" the tag with that sentence is on the center of the carpet, as he reads it the tag is on the border. But in the close-up of the tag with electricity around it the tag is on the center again. Later as Dipper reads all the entire tag it was on the border again.
 * For a split second, when Dipper (in Mabel's body) was screaming while looking at the mirror, one of his eyebrows disappear.
 * When the twins are discussing about the body swap, their reflections are not seen in the mirror.
 * When Dipper (in Mabel's body) enters the kitchen to first give Stan the rock sandwich, the cereal box is missing until he pours it over himself.
 * When Grenda puts lipstick on Mabel (in Dipper's body), she puts it around the lips. But when she and Candy finish put make-up on her and when Mabel and Dipper swap bodies the lipstick is all over the lips. Also, the lipstick changes size and lining.
 * When Dipper (in Deputy Durland's body) and Mabel are fighting, Dipper makes a sound but Keith Ferguson (Deputy Durland) is heard instead.
 * Soos wasn't seen biting part of the door until the close-up of him is showing.
 * The arrows on the Electron Carpet switch from counter-clockwise to clockwise at some points.
 * When Waddles (in Soos's body) is eating the tissues, a tissue is seen on the corner of the table. Then when Grunkle Stan calls him the tissue disappears.
 * Throughout the episode, whenever it's showing Waddles (in Soos's body) its lacrimals are light purple rather than white.
 * When Old Man McGucket corners Soos (in Waddles's body), the puddle of mud disappears.
 * Before Candy says "Boys make me think about kissing!", the pillow Grenda throws at her is pink, but when Grenda does throw the pillow, it's green.
 * When Dipper first lies down outside, he is far from the totem pole. In the next shot, Dipper's pillow is up against the totem pole.
 * When Dipper says that the carpet switches minds, his eyebrows are gone.
 * When Mabel and Dipper are tackling each other in their room, the mini Eiffel Tower that Grenda broke at the beginning of the episode is perfectly fine.
 * When Dipper first enter the room he read the back of the carpet's tag which says "Experiment 78." After switching bodies the back of the tag says "Electron Carpet."
 * When Candy is taped to the wall you see that the mini Eiffel Tower is perfectly fine but when Dipper comes back in and asked what happened Mabel said Grenda broke it but if anyone broke it is would have been Candy.
 * When Dipper and Mabel are arguing and tackling each other at one point the inside on Dipper's hat is black but in the next shot it's back to blue.
 * When Dipper is in Mabel's body, the usual bags under his eyes have found their way over to Mabel's face. However, at many times in the episode, Mabel (in Dipper's body) has the same bags under her/his eyes before the switch.

Boyz Crazy

 * The radio Robbie plays his CD on disappears but reappears in the next scene.
 * For a second, the symbol on one of the Pitt Cola cans is incorrect.
 * When Stan turns to tell Dipper a story about music the design on his fez is different for a split second.
 * When the camera zooms in after Stan puts the CD in the record machine then out again Stan appears to be on the same side of the table as Dipper but earlier they were on opposite sides.
 * The music producer steps on a flower Soos was watering. Later, when the goat is eating his license plate, the flower disappears.
 * When Mabel is blocking the door her headband is gone, then from the back of her head it appears again.
 * There is a part in which Grenda is shown without any lip-gloss on her lips, but then some lip-gloss appears on her lips.
 * When Wendy wears a coat, she zips up it, but in next scene it is unzipped.
 * When Grunkle Stan threatens to rewind Robbie's face, the speed is at 16.5. But when Dipper rewinds the record, the speed is just above 45.
 * When Candy, Grenda and Mabel find the boys inside the cage, there is a frame in which Candy's skirt disappears.
 * The license plate on Bratzman's car says '2013' when he first pulls up, but when Gompers chews on it after he drives away it says '2012'.
 * In the introductory shot of Thistle Downe, the shot wasn't cropped properly, so the edge of the Pitt Cola poster ends off oddly.
 * When Grenda says 'It's Grenda time" and kisses the poster she still has the lipstick, but the eyeshadow is gone.
 * When Mabel came to apologize to Grenda and Candy, in one frame her mouth disappears.
 * When Dipper first walks into the kitchen the only chair there is the one holding up a box of The Brown Meat. But when Stan invites Dipper to tell him his problem, another chair appears for Dipper to sit on.
 * When Dipper and Stan go to Lookout Point, Stan has his less formal attire on. However when they are in the Stanley Mobile, he has his usual outfit on.
 * The money symbol on Bratzman's hood, changes to something that resembles an upside down number five.

Land Before Swine

 * Up until the tourists realize Stan is ripping them off the children aren't holding anything. But once they do it cuts to them throwing down souvenirs before leaving.
 * When Soos picks up the yarn in the abandoned mines, it ends by Mabel's feet. In the next scene, Soos is wrapping around a large ball.
 * Stan originally straps Waddles to his back, but when he appears punching the pterodactyl, Waddles is strapped to his front.
 * Stan's clothing was torn from his fall and battle with the pterodactyl. However, his clothing is undamaged when they leave the abandoned church.
 * Mabel had her backpack on all the way up to Old Man McGucket getting eaten. It cuts to what Stan and Waddles are up to, and when it returns to Mabel, Dipper, and Soos, she no longer has it.
 * When the pterodactyl is charging at Stan from the air the Huggy Wuvvy Tummy Bundle is nowhere to be seen.
 * After Stan jumps off the pterodactyl and climbs up the edge of the cliff he has wounds on both sides of his chin, but when he turns to talk Mabel he only has a wound on the right side.
 * In the credits, Stan says he has 4 aces, but the ace of hearts is on the table.
 * At the very beginning when Deputy Durland is playing Cap'n Brain-Teasers' Fun Maze one of the shark's teeth are golden.
 * Waddles is shown eating a piece of Stan's pant leg. One, fraction of a second, frame later it literally disappears from his mouth.

Dreamscaperers

 * When Bill is about to finish off Mabel and Soos. Mabel's skin that was supposed to be green changes to her normal skin color.
 * When Gideon gets the deed to the Mystery Shack, he holds it up, then after he lowers it for a second, he raises it again and shouts "Now get off of my property!" during this, on the deed, the dotted line under Stan's signature disappears.
 * The candles around the sleeping Stan disappear when the gang leaves his mind.
 * The hat on sleeping Stan's head disappears when the gang leaves his mind.
 * Waddles and Wendy appear to be completely missing, even when the Pines family and Soos run out of the Shack.
 * When Gideon was on his walkie-talkie, Soos, Dipper, Mabel, and Stan were inside. A few shots later, they are suddenly outside the shack.
 * When the memory of the combination falls into the Bottomless Pit, Stan is holding a cane which he didn't have in that episode. More importantly, it's just a regular cane instead of his usual 8-ball cane. Also, it oddly looks like the cane Bill was holding.
 * In the memory of Stan entering the secret room there are boxes on top of the vending machine, which are not seen in that episode. (although this memory may be of another time Stan entered the room)
 * In the memory of Stan entering the secret room he goes inside and comes out with a lantern, but in the actual episode he went inside with one. (although this memory may be of another time Stan entered the room)
 * The code Stan used to enter the secret room is different form the one in "Tourist Trapped." (although this memory may be of another time Stan entered the room, and had changed the combination at some point)
 * In the memory of Stan that Dipper enters, when he first enters it Soos's T-shirt is the same color as his skin.

Gideon Rises

 * When Gideon first jumps through the paper-covered hoop, he is wearing the mystic amulet that was destroyed in "The Hand That Rocks the Mabel." In the next shot he is back to his normal white necktie.
 * When Gideon unveils the Gideon Land model his white neck tie is green. It then goes back to white when it shows him with the Gideon Popsicle behind the Gideon Land model.
 * When Wendy mounts her bike, the outline around Dipper's right eye is briefly miscolored.
 * In "Little Dipper," the maze page is the page before the height altering crystals one. In "Gideon Rises," the Gremloblin page is before it.
 * The orientation of Gideon's face on his pins is shown wrong twice. Once when Shandra Jimenez is interviewing Gideon and again when Stan reveals that they are cameras.
 * When Gideon first gets Journal 3, and picks it up, the thumb occasionally disappears.
 * At the end credits, the TRUST NO ONE page is on the wrong side of the book, as in "Tourist Trapped" it's on the left, not the right.
 * In the scene when the Mystery Shack is being repaired, Mabel's usual pink shooting star sweater is purple.
 * Just before Gideon commands the gnomes to take the twins away his usual white tie changed to green.
 * When Gideon is explaining the journals to his father; the mysterious man is burying the journal where Dipper found 3, but the mysterious man is burying 2 which is supposed to be 3.
 * At the exact moment Gideon says "subdue them!" to the twins, his right foot is split in two.
 * When Gideon asks Old Man McGucket if the Gideon-bot is completed he has 2 and 3. However, when he enters it, the books are gone. Later, when Dipper and Mabel defeat him, 3 is revealed in the robot, as Dipper found it in the rubble, and Gideon held 2 in his clothes.
 * In the newspaper at the end, in the photo of Gideon behind bars, he has 4 fingers on each hand instead of 5.
 * At the end of the episode when Mabel is trying to cheer up Dipper there is a green suitcase next to her, but when she gets off her bed it disappears.
 * Although Shmebulock nodded yes when Jeff asked him if "Shmebulock" was the only word he could say, it isn't, because in "Tourist Trapped" he said "Queen" with the other gnomes.
 * Adjusting the contrast on one view of the Universe Portal reveals a colorless black dot to the right of the machine.
 * Near the end there is a pan-down of a cross section of the building. We pan down from the twin's room, with their window facing out to the night sky. Directly below it is the gift shop, seen in a view facing the vending machine, toward the building's interior. This is an impossible mutual orientation for the two rooms.

Candy Monster

 * The number of golf clubs Dipper has changes, he had three when he tried to trap the creature and had six near the end.
 * Although the card at the beginning says that the recording is meant to be named "Dipper's Guide to the Unexplained," at the end of the short Dipper says "Dipper's Guide to the Supernatural."

Stan's Tattoo

 * Although the title card at the beginning says that the recording is meant to be named "Grunkle Stan's Tattoo," Dipper says "Grunkle Stan's Secret Tattoo."
 * Dipper says that Stan never takes off his under shirt, but he takes it off twice in "Dipper vs. Manliness" and nobody noticed anything.

Mailbox

 * The mailbox tells Dipper that the end of the world is in 3012, even though the years end up going to numbers such as 207̃012, as seen in "The Time Traveler's Pig."

Lefty

 * The robot's right arm and right leg completely disappear as he is turned around by Dipper.

Tooth
None

The Hide Behind
None

Mabel's Guide to Dating
None

Mabel's Guide to Stickers
None

Mabel's Guide to Fashion

 * Mabel is shown using a black cell phone. In "Dipper vs. Manliness" she said she didn't have a phone.

Mabel's Guide to Colors

 * When Dipper and Candy are setting up the mirror, Dipper's nose is the same color as the rest of his face.
 * The window through which Stan sees the rainbow has never been seen in his office before and doesn't seem possible to be facing outside.

Mabel's Guide to Art

 * In the last few seconds of the short, when Mabel is being attacked by cats, her braces are missing.

Fixin' it with Soos: Golf Cart

 * When Soos goes to fix the golf cart's inside it is totally repaired.
 * When the golf cart successfully jumps Stan's car, "STNLYMBL" on the car license plate is mirrored.

Fixin' It with Soos: Cuckoo Clock
None

TV Shorts 1

 * During the disclaimer at the end of the Mystery Shack commercial, the statement reads: "In the even of no tip, you will be escorted from the premises." "Event" is misspelled.

TV Shorts 2
None

Mabel's Album of Memories

 * Mabel  slushes herself up then climbs on the wall to open the outdoor vent however there is no slush on her hand when she opens it.

The Petting Zoo

 * Mabel said she doesn't have any pictures of the gnomes in "The Legend of the Gobblewonker," but a picture of a gnome is shown in Mabel's album.