List of goofs/Season 2

Scary-oke

 * Stan activated the Universe portal in "Gideon Rises" by pushing the lever in front of it to the left. But during a full shot of the portal room at the beginning of this episode, the lever is seen facing the right.
 * When Agent Powers and Agent Trigger look at their screen after Stan activates the portal, Agent Powers sits left and Trigger sits right. They change while the map appeared
 * When Wendy comes into the Mystery Shack after Stan, Mabel, and Dipper are announcing the After-Party, her horn still sounds despite the button not being pressed.
 * When Wendy enters the shack at the announcement of the after-party, she is wearing her name tag. However, while she is leaving with the crowd, her name tag is not seen.
 * When Dipper and Mabel are in the attic, and Mabel is claiming that there is nothing left to discover about the journal, there are only watermelon seeds on the neck and sleeves of her sweater; the front of the sweater is completely missing the watermelon seeds.
 * When Soos sees the government agents pull up, they park outside the gift shop's side window. When the agents leave, their car is parked in front of the gift shop.
 * When Lee, Nate, Tambry, and Thompson arrive at the party, Lee is wearing a sleeveless shirt.  In the next shot, it has short sleeves.  When all four are seen dancing, he is sleeveless again.
 * Dipper mispronounces the spell he uses to raise the dead. In the journal, the incantation's second line reads "Diablo Dominium," but Dipper reads it as "Diablo Dominus."
 * In the shot of the teens dancing, Tambry is wearing her regular day wear instead of the party outfit shown earlier.
 * During the rap scene, the number of Blubs' fingers changes.
 * Lazy Susan's lipstick is missing  in two scenes; one where she is entering the Mystery Shack with a pie, and when the ground is shaking from the zombie invasion.
 * Mabel's hair poof color changes multiple times, from brown to pink, when the zombies attack.
 * During one of the shots after the zombies destroy the golf cart, some colored lights can only be seen for one shot above the horde with Soos, as well as some orange and yellow flags.
 * When Stan's talking to himself about Dipper in his underground lab, the desk, which presumably showed Stan's tattoo, looks different. The altocumulus cloud-looking symbols are upside down and connected to the main body of the symbol, and there are circles in the middle of the outward pointing arrows.
 * When Stan sees himself in the reflection of  1' s hand, the reflection is not reversed.
 * In the same scene, 1 is shown with a monocle and ripped back cover, which are unique to 3.
 * During "Taking Over Midnight", when the three are singing "We're queens of the disco!", Dipper steps up, followed by Mabel and then Stan, but when the camera zooms out, the order changes to Dipper, Stan and then Mabel.
 * After singing "Taking Over Midnight" by &NDRA, Stan's fez appears while yelling "Deal with it zombie idiots!" It then disappears again in the next shot.
 * The karaoke machine only has one microphone plugged in when Stan, Dipper, and Mabel are singing.

Into the Bunker

 * Wendy has two left arms when she reaches for some popcorn.
 * In the same scene, in one frame, Dipper's mouth is completely displaced from his face.
 * The stuffed animal Wendy pulls from her bed's corner wasn't there in the previous scenes, nor shows up again in the following scenes.
 * Even though the Shape Shifter turned into a Hide Behind, the journal had no clear picture of it.
 * At the end of the episode, several fireflies are seen buzzing around, despite the fact that fireflies are not native to Oregon.
 * In the scene in which Dipper was going to find another way out of the bunker, he grabs Wendy's right hand. In the following shot, he's holding her left hand.

The Golf War

 * While Pacifica is insulting the Pines family, Dipper does not have a putter. But when he decides to make a comeback, he is leaning on a blue putter.
 * The right wing of the golf cart driven by the royal employee goes through the lamp post as he drives around it.
 * When Dipper first hears noise coming from inside the windmill, the wood covering has a design on it. When he approaches with Mabel to tear it off, it is plain.
 * The map of the course is not an accurate representation. For example, the windmill and the pirate ship are close together, but in the map they are widely separated.
 * When Dipper is talking with Mabel, his mouth is over his vest.
 * When Mabel is apologizing to Pacifica, in one frame her braces remain the way they would be when her mouth is wide open, even though her mouth partly closed.

Sock Opera

 * When Dipper and Mabel are leaving the Gravity Falls Library, they forget the laptop on the desk.
 * When Gabe visits the Mystery Shack, Mabel's braces disappear when she begins laughing nervously.
 * When Bill in Dipper's body stopped smacking the drawer onto his arm he had two forks sticking out of it, but when he left they disappeared.
 * When Bill first possesses Dipper, his eyebrows disappear.
 * During the show, when Dipper (as a ghost) is doing the kiss scene of puppets Mabel and Gabe, there is a hearth-shaped background close to the socks, but when the camera changes the background is no longer there.
 * In the theater Wendy and Bill are sitting in the same seat at first, with exactly one free seat to their right. A few seconds later they are sitting in two separate seats and there is still a free seat to their right.
 * Several times throughout the sequence where Bill possesses Dipper, the password bars disappear.

Soos and the Real Girl

 * When dying his Abeulita's hair, the foil is originally silver, but when she walks away it is bright orange.
 * After Soos leaves work and it cuts to "First Person Puncher," everything is pixelated; the TV, walls, figurines.
 * During the scene in which Soos is first trying the game and says "I'm learning, and games are making it fun", his eyebrows are misplaced for a fraction of a second.
 * The "HE's GOT ATTI-CUBE!" poster in the door of Soos' room shows a prominent COOLCUBE logo in the upper right corner when we first see it.  In subsequent shots the COOLCUBE logo is missing.
 * During the scene where Mabel and Dipper drag Soos away from his room, Mabel's cheeks have outlines on them for two frames that flicker back and fourth.
 * When the door to Hoo-Ha Owl's Pizzamatronic Jamboree closes, it is covered in pits before it is hit by any skee-balls.
 * In the scene where Soos and the others are hiding behind the toppled arcade cabinet, the character peeking over the fortress wall on the side of the cabinet changes from a peach color to red in one short scene.
 * In Hoo-Ha Owl's Pizzamatronic Jamboree, the graphics for Star Battle appear on the unit for First-Person Puncher.

Little Gift Shop of Horrors

 * While Stan is attempting to get the traveler to come into the Mystery Shack, his mouth overlaps his nose for a frame.
 * When the Pines first approach the Hand Witch's table, the stall in the background says "Lots O Pots." Later is changes to "Pots Aplenty."
 * When Stan mocks Dipper's concern about a curse, the stalls in the background change. Instead of Lazy Susan and Old Man McGucket's stalls, Pots Aplenty and Cheep Cheep Tires appear. Additionally, they are transposed (Pots Apently was on the right of Cheep Cheep Tires next to the witch's stand).
 * In the scene in where Mabel and Dipper first see that Waddles is now a genius, the machine that he rolls in on is layered incorrectly with a nearby pile of books.

Society of the Blind Eye

 * Lazy Susan's apron stain appears on the right (her left) briefly when her hands are being clasped to the chair. Not long afterwords, when her hands are being unclasped, the stain is again incorrectly depicted on the right.
 * Blind Ivan's tattoo patterns change multiple times.

Blendin's Game

 * In the cold open, Mabel's sweater does not have any graphic on it, which is later shown to be a doughnut.
 * In the beginning of the episode, Stan has a bandage in his hand. During the laser tag scene, it disappeared.
 * At the end of Globnar, cuffs appear on Blendin, although they were not there in the previous shot.
 * The postcard Soos is looking at is clearly of New Orleans, but in the next shot it has changed to a postcard of/from Las Vegas.
 * Toby's mouth is misplaced in his reflection.
 * The mirror reflects Toby as being much closer to it than he actually is. It also does not reflect the railing that is right in front of it.
 * The photo and signature on Soos' drivers license change drastically between shots