Adult Fear: "Tourist Trapped" contains a quite plausible child-abduction scenario.
"Gideon Rises" has a subtle but very painful one: Stan is forced to realize that, having lost the Shack, he cannot take care of Dipper and Mabel. This is evident when we see him talking with Dipper and Mabel's parents; he lies to them about their current condition and we see him realize that they cannot live with Soos for the summer since there is little income and little food. This strikes a chord for many parents or guardians who fear they may have to surrender their kids to other family members or social services because they can no longer take care of them.
Agent Mulder: Dipper and Soos, the former spurred on by a supernatural compendium. For example, in "Tourist Trapped", Soos says the mailman's a werewolf and believes Dipper's theory about Mabel's boyfriend being a zombie, a theory Dipper came up with after looking though the book.
Air-Vent Passageway: Dipper uses one to get into the convenience store in "The Inconveniencing".
All There in the Manual: Lots of info on characters, secret codes, screenshots and animated GIFs of 4 and beyond, as well as information taken from online games and otherwise, were being thrust into the public's hands before most folks could barely watch Episode 2.
Dipper's book serves an in-series example, seeing as it has information on all the creatures, various spells, and even a clue to a conspiracy.
Ambiguously Evil: Stan, all the frigging time. It only gets even more ambiguous in "Gideon Rises". What the hell is he planning?
Ambiguously Gay: Tyler, the Cute Biker. He shows up out of nowhere to cheer on Manly Dan beating up a fish. He also shows up in the restaurant where Mabel and Gideon go on a date, calling the two adorable. His shorts are... pretty short, and he has visible eyelashes, which otherwise only female characters have. Also, in "Irrational Treasure" he and Manly Dan are briefly seen sharing a plate of meat between themselves. In "Boyz Crazy" he, along with Old Man McGucket, are in the audience at the Sev'ral Timez concert.
Sheriff Blubs and and Deputy Durland act very much like a married couple most of the time.
Ambiguously Jewish: The Pines family. Mabel and Grunkle Stan occasionally use Yiddish words ("mazel tov", anyone?). Dipper and Stan fit a couple of stereotypes respectively. there's also the fact that "Pines" is an eastern Ashkenazi Jewish surname. This can all be Author Appeal given Alex Hirsch's Judaic background.
"Bottomless Pit" has Mabel utter the line "Sweet Moses!" Stan says it in "The Land Before Swine".
Animation Bump: Pretty much the entire intro is drawn with more detailed shading and more fluidly animated than the rest of the show. More evident in some shots than others - for example, Mabel plugging her sweater into the outlet is drawn with great detail, and Dipper getting scared and dropping his candle is extremely fluid.
Which is not to say that the show itself is animated poorly. The sea monster in "Legend of the Gobblewonker" is particularly nice.
Rumble in "Fight Fighters", due to being animated entirely by Paul Robertson.
Heck, an average episode beats out most cartoons' opening titles.
Anti-Mutiny: What the clone Dippers try to do to Dipper in "Double Dipper". When Tyrone realizes that the original plan wasn't working, they laugh it off and share a soda instead.
Arbitrary Skepticism: In "Bottomless Pit!", Grunkle Stan still states that everyone's stories are far-fetched, even though he is falling through a bottomless pit even as he speaks, and even lived through one of the stories.
Arc Symbol: A simple drawing of an eyed pyramid with limbs and a top hat is all over the series, from the opening credits to the Mystery Shack's windows. He turns out to be an extremely powerful demon named Bill Cipher.
Big Brother Instinct: Dipper, most prominently when warning Mabel about her new boyfriend and driving a golf cart like crazy when he thinks she's in danger. Mabel also has had several instances of Big Sister Instinct. For the record, Mabel is older by five minutes.
Soos also seems to have a bit of this for the twins, despite not being an actual relative.
Also, in "The Land Before Swine", when Dipper finds out that the pterodactyl took Waddles, he is dead-set on helping his sister get her beloved pet back.
The spell Gideon uses (also in Latin) to release Bill Cipher, however, makes much more sense in English: "Triangle, I invoke you! I come to the defensive barrier of the mind! I will see the barrier destroyed!"
Bland-Name Product: "Pitt" brand soda, possibly a parody of the real-life brand "Mr. Pibb". It's been sighted on a machine inside the haunted convenience store, and Dipper and Tyrone drink it at the end of "Double Dipper".
Or, more likely, "Cott". Cott's is also almost immediately associated with orange-flavored pop, and what's the logo seen on a Pitt vending machine?
It's a peach. Pitt Cola is shown in almost every episode, and the Gravity Falls site say it's a peach flavored cola with an actual pit inside the can.
Fun fact: The soda is very probably named after the show director Joe Pitt, whose name you can find in the credits.
Blush Sticker: Mabel and her friend Candy have permanent circles of pink on their cheeks.
Bookcase Passage: Shown in "Tourist Trapped". Stan has a passage hidden behind his vending machine. Where does it lead to? An underground research facility, where Stan has been holding Book #1 for years and has been waiting for Book #2 (retrieved after Gideon was arrested) and Book #3 (took it from Dipper when Dipper showed it to him). He needed them to summon something. What is it? No one knows... until season 2 premieres.
Book Ends: The ending of "Tourist Trapped" (the pilot) shows Stan entering his secret vending machine passage, and the ending of "Gideon Rises" (the season one finale) shows Stan entering his secret vending machine passage... revealing that he's been hunting the books for a while, and needs them to summon an ultimate power.
Breather Episode: "The Land Before Swine", considering the episode that immediately follows.
Brick Joke: In Episode 2, there's a Cutaway Gag of Grunkle Stan and the kids forging money, and he remarks that their Benjamin Franklin looks like a woman. Several episodes later the twins find a repository of America's embarrassing secrets that includes a folder about which Mabel remarks: "Oh man, Benjamin Franklin secretly was a woman!"
In "Double Dipper", Soos is the DJ for the party and needs a lightning sound effect for a punchline to one of his one-liners but can't find it on the soundboard. During the credits, we see him go over the entire soundboard and find the lightning on the very last key to which he cheerfully exclaims: "Found it!".
Rather than feeling resentful to the original for putting himself above them or trying to take over, the army of Dipper clones clones are totally in sync with the original - to the point where they have the same ideas and thoughts at the same time and tend to totally get along. They have no problem with helping Dipper fulfill his plan even though they won't be benefiting from it, since they're also Dipper and thus agree with the plan in the way he thought of it. It works out fine until Dipper has an epiphany they didn't and decides he doesn't want to follow the plan any more.
They are aware that they are expendable and don't seem to mind - #2 is even reassuringly points out before the plot happens that if they do go nuts Dipper can just get rid of them easy using water - and they treat being disintegrated as more of an inconvenience than anything.
They totally avert Kill and Replace, even when they briefly revolt against Dipper. At no point do they even think of replacing the original Dipper for more than a few minutes, and make sure he's comfortable while they do so.
In "Boyz Crazy", it turns out all the singers in Sev'Ral Timez are clone lab rats.
Cloudcuckoolander: Quentin Trembley. Full stop. Mabel, Old Man McGucket, and possibly Soos count as well.
Continuity Nod: Besides the Myth Arc hints, there's the time when Dipper asks Mabel if they've got any pictures of the gnomes they saw the first episode and Dipper apologizing to Toby Determined for accusing him of murder in "Headhunters".
The "S" on the Mystery Shack sign was knocked off in "Headhunters". It has since yet to be fixed and appears broken in every following episode.
Mabel shows her scrapbook in "Dipper vs Manliness". You can see that it has a picture of the beheaded wax Stan from "Headhunters".
In the episode "The Time Traveler's Pig", the pilot of the wagon on the Oregon Trail exclaims "By Trembley!"
In "The Time Traveler's Pig", the show has a moment for all the previous episodes.
In "Carpet Diem", Waddles can be seen wearing the top hat Quentin Trembly gave to Mabel.
In "Boyz Crazy", Dipper sees Mabel dancing happily and comments about if she ate Smile-Dip again.
In "Irrational Treasure", Mabel comments that she doubts Deputy Durland can read. In "Bottomless Pit" Durland asks Stan to teach him to read.
In the online game "Mystery Shack Mystery", one of the codes is EVER SEEN STAN'S TATTOO? Indeed, he has one, but only a small portion of it is ever seen. In "Dreamscaperers", when Bill remembers Stan Pines, a full picture of his tattoo is shown.
One of the Dipper's Guide to the Unexplained shorts focuses on the kids trying to see his tattoo, and we even get another continuity nod in the short when we see Dipper's forehead and birthmark again for the first time since Double Dipper.
Crazy-Prepared: Dipper brings 17 disposable cameras for a monster hunt in episode 2. This is because he's Genre Savvy enough to realize that cameras keep getting destroyed or lost during monster hunts.
Creator Cameo: Alex Hirsch provides the voice for Grunkle Stan, Soos, Old Man McGucket, Bill Cipher, Jeff the Gnome, Quentin Trembley, and Paper Jam Dipper.
He also appears briefly on the television in "Bottomless Pit!"
Credits Gag: There's a different cryptogram in the ending credits of each episode. To decode the cryptograms, each letter must be replaced with the letter that comes three spaces before it. The first episode's cryptogram reads "ZHOFRPH WR JUDYLWB IDOOV." Once decoded, it reads "WELCOME TO GRAVITY FALLS."
Once decoded, Episode 2's cryptogram reads "NEXT WEEK: RETURN TO BUTT ISLAND".
Episode 3: "HE'S STILL IN THE VENTS".
Episode 4: "CARLA, WHY WONT YOU CALL ME?".
Episode 5: "ONWARDS AOSHIMA!"
Episode 6: "MR. CAESARIAN WILL BE OUT NEXT WEEK. MR. ATBASH WILL SUBSTITUTE."
Caesarian and Atbash are both ciphers, Caesarian being the three-letters-back code, while Atbash is the Z=A-Y=B-etc. code. So, there's a technical break in the mix.
Once decoded using the Atbash code, Episode 7's crytopgram reads PAPER JAM DIPPER SAYS: 'AUUGHWXQHGADSADUH'". The cryptograms in later episodes are also solved using Atbash.
Episode 10: SORRY, DIPPER, BUT YOUR WENDY IS IN ANOTHER CASTLE.
Episode 11: THE INVISIBLE WIZARD IS WATCHING.
Episode 12: BROUGHT TO YOU BY HOMEWORK: THE CANDY.
Episode 13: HEAVY IS THE HEAD THAT WEARS THE FEZ.
Episode 14 supplied a number substitution coded message (gematria), with dashes between letters and regular punctuation left as usual. The translated message reads: NEXT UP: "FOOTBOT TWO: GRUNKLE'S GREVENGE"
Episode 15: VIVAN LOS PATOS DE LA PISCINAnote LONG LIVE THE POOL DUCKS
Episode 16: BUT WHO STOLE THE CAPERS?
Episode 17: HAPPY NOW, ARIEL?
Episode 18: IT WORKS FOR PIIIIIIIIIIIIIIIIIGS!
Episode 19: TO BE CONTINUED...
Episode 20: Episode 20 actually has two of these, one of which is in the footage above the credits and is needed to decode the normal one. first is an A 1 Z 26 cypher that translates REVERSE THE CYPHERS, which is a hint for when we see the second, which is another A 1 Z 26 cypher, but it's reversed like an Atbash. as in Z=1, A=26. so, once you translate it knowing this, you get a Caesarian cypher that can be translated with the usual 3 letters back to spell out SEARCH FOR THE BLINDEYE
Deliberately Monochrome: Played with in Episode 8. Dipper holds up a postcard of the town square, then lowers it to a sepia-toned town square. He was really just looking through some very dirty glass that was being carried across the street.
Disproportionate Retribution: Played for Laughs with Old Man McGucket's giant robots, but a much darker example occurs when Gideon's response to Dipper breaking up with him in Mabel's stead is to use his telekinetic powers to try to cut out his tongue.
Don't Explain the Joke: In "The Legend of the Gobblewonker," when trying to recruit fishing buddies, Stan interrupts a man about to propose to his girlfriend with this joke: "My ex-wife still misses me, but her aim is getting better!" After repeating the punchline, he explains, "It's funny because marriage is terrible."
Early-Bird Cameo: Lazy Susan appears in the diner for a moment in the pilot, and isn't formally introduced until five episodes later.
A picture of Robbie can be seen posted on the bulletin board among the other suspects in "Headhunters".
Li'l Gideon is featured in a magazine advertisement two episodes before Dipper and Mabel actually meet him.
Mr. Poolcheck appears in the Skull Fracture bar an episode before he is introduced in "The Deep End".
Early-Installment Weirdness: The first episode was narrated by Dipper and ended with him writing in the journal, kind of like an episode of Doug. After that, the narrations seem to have been dropped.
Earworm: It's mentioned in-universe that the songs of Sev'ral Timez are quite catchy.
Easter Egg: The messages in the credits at the end of every episode. To decode them, you have to send each letter "three letters back", as explained when the intro is played backwards. JHW WKH SLFWXUH?
Extreme Omnivore: Implied when we see one of Mabel's drinks contain a strange cyclops Troll Doll and several dice, all in a green fluid.
She also once ate a whole tube of toothpaste because "it was so sparkly".
Old Man McGucket is even more so, having eaten such things as books and a live pterodactyl.
Eye Colour Change: Mabel's eyes turn green when she's had too much Smile Dip. Additionally, looking into the Gremloblin's eyes causes the eyes of two tourists to match the creature's bright yellow ones.
F - O
Face Doodling: Stan writing the word "goober" on Dipper's forehead in "Stan's Tattoo".
The Foreign Subtitle: Along with the Japanese name seen above, this show has also been given the subtitle Un Verano de Misteriosnote A Summer of Mysteries in most Spanish-speaking countries. Brazil used a Portuguese-translated version of the title.
In "Tourist Trapped", when Dipper is trying to warn Mabel about Norman, he accidentally opens up to the gnome page of the journal instead of the intended zombie page. Turns out his first guess was more accurate.
At the end of "Tourist Trapped", Stan uses a vending machine to access a secret room. That surely won't come into play later.
As of season one's finale, it's revealed that behind that vending machine is a secret passage to a laboratory containing something that could only be activated when all three books were gathered.
During Lil' Gideon's Villain Song in "The Hand that Rocks the Mabel", he gets everyone to stand up after holding his amulet. Turns out, his amulet gives him Psychic Powers. Dipper was forced to stand up against his will, making Dipper question what just happened.
The Number 2 book.
There's also a newspaper in one of the earlier episodes which has an ad for a "child psychic".
In Irrational Treasure, the top secret document mentions a giant, evil, time-traveling baby from another dimension being frozen in a glacier in Antarctica. Fast forward to "The Time Traveler's Pig", where we see said giant evil baby apparently ruling over the future.
Four-Fingered Hands: Most of the characters in the show have four fingers, but some characters, like Stan and Soos, have five fingers on each hand.
Making it even stranger is how the cover of Dipper's book features a six-fingered hand.
Four Temperament Ensemble: Dipper is melancholic, Mabel is sanguine, Grunkle Stan is choleric, and Soos and Wendy are both phlegmatic.
You get a shot of Bigfoot◊ in the opening credits. Blink and you'll miss it.
Dipper's book has a lot of these, in the forms of foreshadowing, creepy info about the local monsters, and the occasional joke.
"Knock! Knock! Who's there? THE FORCES OF EVIL!"
At the end of the opening credits, you see a page from the journal with the words "VWDQ LV QRW ZKDW KH VHHPV". When decoded it reads "STAN IS NOT WHAT HE SEEMS".
Episode 8's document about Nathaniel Northwest can be read in full.
Blendin Blandin, the time traveler from Episode 9, can briefly be seen in the first◊ three◊ episodes◊, fixing the paradoxes the twins caused.
Episode 16- Pause at exactly 12:34, when Stan opens the book to the page about the pituitary gland, and you'll find a "three letters back" code at the bottom: "SXEHUWB LV WKH JOHDWHVW PBVWHUB RI DOO. DOVR: JR RXWVLGH DQG PDNH IULHQGV" (PUBERTY IS THE GREATEST MYSTERY OF ALL. ALSO: GO OUTSIDE AND MAKE FRIENDS).
When Bill Cipher says "I know lots of things. Loooots of thiiiings." his triangle flashes countless images, and if you pause them you can see, in that order: John F. Kennedy (Implying something), Blurry UFOs, Mayan scriptures, one of the Mysterious 3 book that Dipper owns, the moon landing, one of the pages of the 3 book, a skull with a cigarette, Stonehenge, The Pyramids, Stan going for his secret vending machine door, The Sasquatch seen in the opening, another page of the book, Crop Circles, the secret room where the twins found Quentin Trembley,A statue of Nathaniel Northwest, a unknown location called "The Lone Penn", various clocks, what seems to be a abandoned warehouse, a maximum security prison, then it repeats the blurry UFOs and the blank scriptures.
From the same episode, pay very close attention to the picture on Bill's face when Gideon mentions Stan.
Generation Xerox: The monster from "Boss Mabel" had his power reflected back at him showing him his worst fear he sees himself with glasses looking into a mirror, while the reflections screams "You've become your father!" He proceeds to scream and run away.
Great Big Book of Everything: Dipper finds a book in "Tourist Trapped" with a six-fingered hand and a "3" on the cover; it gives clues to all the strange happenings in Gravity Falls. The book ends abruptly in the middle and the author is unknown. Li'l Gideon has a similar book with a "2" on it.
The Great Politics Mess-Up: Considering that Rumble McSkirmish is from an 80's video game, he believes the Soviet Union is still around.
Improvised Weapon: When they encounter a monster, the twins typically just use whatever they have on hand. Weapons so far include a shovel, living gnomes, the afore mentioned leaf blower, a fire iron, electric candles, lamb shears, a flashlight, props from a costume store, a mirror, and water balloons.
Just Following Orders: The police didn't really want to haul Dipper and Mabel off to Washington, but they had their orders.
Just You And Me And My Guards: Dipper and Robbie decide to settle their differences with a fight. Dipper, being a noodle-armed weakling, enlists the help of martial arts video game character Rumble McSkirmish to scare off Robbie. Granted, Rumble doesn't know the difference between scare and fight.
Karma Houdini: Almost happens to Pacifica Northwest in "Irrational Treasure". The twins found evidence of who actually founded Gravity Falls, but Mabel's willing to let it go. Dipper, however, isn't going to let this happen, and so, at the last second, right before she leaves, he gives her the evidence, which doesn't exactly please her.
Pacifica:What!? Mom! Dipper: Man, revenge is underrated. That felt awesome!
At the end of the one of the Cold Opens, the Pines decide to go watch tv. As they walk offscreen, Mabel cheerfully says "my favorite part is the theme song." Cue the opening and Instrumental Theme Tune.
Libation for the Dead: Dipper pours some of his soda on the roof when Tyrone commits unintentional suicide.
Love Triangle: Dipper and Robbie both vie for Wendy's attention, with both succeeding and failing at different times.
Lying Finger Cross: In the episode "Fight Fighters", Mabel makes a promise to Grunkle Stan and puts on a sweater with a hand doing the "Scout's honor" gesture on the front. When she turns her back to the fourth wall we see the back of her sweater has a hand with its fingers crossed.
The Magazine Rule: The characters have some interesting magazine subscriptions, such as Wendy's Indie Fuzz and Lake Ranger McGucket's Stoic Monthly.
The Makeover: The girls try to give one to Dipper while having a sleepover.
Man Child: Soos. He's even described this way in Disney Channel's official promotions.
Out of Order: A bizarre case where the production order is off but the airing order matches the writing order. note "Tourist Trapped"'s production number is 105, "The Legend of the Gobblewonker" is 101, "Headhunters" is 102, "The Hand That Rocks the Mabel" is 104, "The Inconveniencing" is 103, "Dipper vs. Manliness" is 106, "Double Dipper" is 109, "Irrational Treasure" is 108, "The Time Traveler's Pig" is 107, "Fight Fighters" is 110, and "Little Dipper" is 111.
Overly-Long Gag: The credits gag from the pilot, the entirety being a gnome vomiting rainbows on an endless loop.
Also, the credits from "Double Dipper," with Soos pressing every sound effect on the keyboard.
And then in "Bottomless Pit," the entire credits gag is Stan falling with an annoyed expression on his face.
P - Z
Pet the Dog: Grunkle Stan gets a moment like this after feeling guilty for insulting Dipper and Mabel and lets each of them take anything they want from the Mystery Shack. In true Grunkle Stan fashion, he tells them to do it before he changes his mind. He also saves Waddles because he wants Mabel to talk to him again and in "Dreamscaperers" when we find out why he's so tough on Dipper.
Ptero Soarer: The "pterodactyl" from "Land Before Swine", which looks like an unholy mixture of all stereotypes, down to the scaly skin, being called a "dinosaur", having eagle-like hindlimbs, leathery wings, having a Pteranodon crest alongside rather mismatched teeth, making chicken-like nests and having zero to no body fat. Strangely enough, though, it walks quadrupedally, like a real pterosaur.
Pun-Based Title: "Headhunters", "The Hand That Rocks The Mabel", "Double Dipper", "Irrational Treasure", "Little Dipper", "Carpet Diem", and "The Land Before Swine".
Dipper and Mabel, during their "awkward sibling hug": Pat, pat.
"Dipper vs. Manliness":
Stan: Tap, tap. (later)Lazy Susan: Wink!
Scenery Porn: It's especially evident in the opening theme, but Gravity Falls is beautiful.
''Scooby-Doo!'' Hoax: Played straight in Episode 2, with the Gobblewonker. Even this straight example is subverted in the final moments of the episode suggesting that there really is a creature, but it just hasn't been seen (yet?). Otherwise averted in most other episodes, with the monster or ghost proving to be very, very real.
Series Fauxnale: The season 1 finale falls under this. Gideon gets exposed as a fraud after taking control of the Mystery Shack, and Stan is revealed to have book #1. He obtains all three to uncover the secrets of the universe.
Serious Business: Mr. Poolcheck puts a lot of angry violent determination in making pool time safe. He, and a bar of angry men, also don't take kindly to prank calls.
Set Right What Once Went Wrong: In "The Time Traveler's Pig" Dipper tries to win a toy for Wendy at the fair, while at another stall Mabel delightedly wins Waddles the pig. Unfortunately Dipper only succeeds in hitting Wendy in the eye with a ball, causing her to go off with Robbie. After obtaining the time machine Dipper makes several attempts to return to the past and prevent the accident, only for it to keep happening in different ways. Eventually Dipper figures out how to make the ball miss Wendy and hit the target, but Mabel has to be there to help him, so she isn't there to win Waddles and Pacifica wins him instead. Seeing how unhappy this makes Mabel, Dipper realizes he has no choice but to go back and restore the original timeline.
Sheet of Glass: In "Legend of the Gobblewonker," when they fly through a pane of glass held between two boats on a lake.
Someday This Will Come in Handy: When Dipper finds the book in the first episode, he sees an amulet but ignores it and continues flipping through the book. Later on, in the fourth episode, it is revealed that the amulet grants the wearer mystical powers. Dipper hasn't realized this yet, however.
And in "Fight Fighters" after Mabel sneaks up behind while he relaxes in his armchair.
Spoiler Opening: Paying attention to the part with the photos in the opening shows Gideon, the gnomes, Blendin Blandin, and the Summerween Trickster. Following this is a split-second image of Bill Cypher.
Spoof Aesop: In "Summerween", Stan learns to focus on what is truly important in life: pure evil!
Status Quo Is God: In "Boss Mabel", Mabel makes a deal with Stan to be the Mystery Shack boss for 3 days and if she makes more money in that time, she becomes the boss for the summer. When Stan returns with no money, she declines after realizing how hard it is to be the boss.
In "Carpet Diem", Dipper and Mabel fight for the newly discovered room to get away from each other. Dipper convinces Stan to let him have the room, but both Mabel and Dipper miss rooming together, so they give the new room to Soos to replace his horrible break room.
Averted in "Dreamscaperers".
Stealth Pun: "Will you join us in holy matrignomey...matri-matriMONY, BLAH, can't talk today..."
The wax figures are cursed to come to life whenever the moon is waxing.
Possibly subverted, as it's not clear if it actually worked. Wendy says afterwards that she doesn't care about the messages and she mainly seems to be upset that his supposedly romantic gesture was just a sleazy attempt at manipulating her.
The Only One I Trust: While Dipper has yet to truly be betrayed by anybody, the journal he finds warns him not to trust anyone in Gravity Falls. Dipper decides that there is one person he can always trust: Mabel.
The Talk: Stan decides to give one to Dipper in the episode "Carpet Diem". Unfortunately, it's Mabel in Dipper's body.
Mabel: Goodbye childhood...
Blink and you'll miss it, but the title of the book Stan uses is Why Am I So Sweaty: Your Body Explained in Horrifyingly Uncomfortable Detail.
Urban Legend of Zelda: There is a picture circulating the Internet of the Slender Man watching Dipper and Mabel from the background in one of the episodes. This is not the case; viewing the episode itself yields no Slender Man.
Though the Hide-Behind from "Dipper's Guide to the Unexplained" looks an awful like the Slender Man.
Vacuum Mouth: The skull from the Tumbleweed Terror pinball game.
Visual Pun: The Mystery Shack's sign has the second S in an odd position or completely taken off, spelling out MYSTERY HACK. Considering who owns the place...
Additionally, Candy dressing like a piece of candy in "Summerween".
Voices Are Mental: In "Carpet Diem", the voices switch along with the characters as they move from body to body.
Vomit Discretion Shot: While the gnome vomits on screen, it throws up rainbows. Taken to extremes when it fills up the entire closing credits of the first episode.
Later, in "Boss Mabel", we see a group of tourists from Stan's point of view. They all appear as walking, talking wallets, and one of them vomits coins.
In "Carpet Diem", Mabel, in Dipper's body, pukes into a toilet.
Weirdness Magnet: It's true that Dipper often goes off looking for the supernatural, but more often than not, the supernatural finds him first.
We Will Meet Again: Used three times so far: the leader of the gnomes, Gideon and Blendin Blandin all swear revenge after being defeated.
Wham Episode: "Dreamscaperers" has Gideon, after the Pines foil two attempts at getting the deed for the Mystery Shack from Stan's safe, instead blows up the safe with dynamite and immediately brings in a demolition vehicle to start tearing down the Shack while the Pines and Soos look on in horror.
In "Gideon Rises," Stan reveals to the townspeople that Gideon was illegally spying on them. Gideon is sent to jail, leaving behind the second journal. Dipper and Mabel decide to tell Stan about the journals... unwittingly giving him all three journals. Because not only did Stan take Gideon's book, he's had the first one all along. The episode ends with Stan ready to open... something.
Wham Line: "After all these years...Finally. I have them all." "Here we go."
He might be saying "...we have them all", but we won't know for sure until the official subtitles are out.
What Have I Become?: In Episode 13, Mabel reaches her breaking point with Soos and Wendy. She tells them for their goofing off in a Stan-like manner, ending up with the fez on her head. She quotes this verbatim when she looks in the mirror.
What Measure Is a Non-Human?: Played for laughs in "Summerween". Soos hits the Trickster and shatters him completely when he was about to kill the kids, and freaks out when he thought he accidentally hit a guy. After Soos eats the Trickster, the episode draws to a close with an EverybodyEvil LaughsEnding as soon as it ends, Soos nonchalantly says "I ate a man alive tonight."
It should be noted that The Trickster was very happy that Soos liked eating him.
Whole Episode Flashback: "Bottomless Pit!" is focused on the characters telling stories, at least one of which we discover actually happened. Also qualifies as a Vignette Episode, as listed above.
Widget Series: Definitely the most off-kilter series on the channel.
The cursed wax figures in Episode 3. They try to murder Dipper and Mabel without hesitation.
Also, in "Summerween", the Summerween Trickster. In fact, he makes it look like he KILLED a child until the end of the episode!
Rumble, the Fight Fighter, was genuinely trying to kill Robbie, endangered Stan and Mabel by toppling the water tower, and beat up Dipper with a nearly lethal combo attack just because Dipper had lied to him.
DOVR, PU. KLUVFK, LI BRX'UH UHDGLQJ WKLV, SOHDVH SXW WKH PHVVDJH DERYH LQ WKH VKRZ DW VRPH SRLQW WR OHW XV WURSHUV NQRZ. note Also, Mr. Hirsch, if you’re reading this, please put the message above in the show at some point to let us Tropers know.