It is also seen in Journal 2 when Gideon is trying to find out how to summon Bill Cipher. The page in the Journal featuring the zodiac looks different than the page featured in the theme song. Some content on the page is the same, and some is different. The page in the journal contains information regarding Bill Cipher, as well as the zodiac. The author states that he had been dreaming of Bill and the symbol for weeks, and he questions the significance of the symbol.
In "The Stanchurian Candidate," Gideon draws the zodiac on the wall of his prison cell in order to summon Bill, so he can make a deal with him.
In "Weirdmageddon 3: Take Back The Falls," Ford reveals that he found these symbols passed down from the natives of Gravity Falls. When each person that correlates with a symbol stands in a drawn version of this zodiac and they hold hands, it has enough power to defeat Bill Cipher. Though the resistance tries to invoke the zodiac's power, Stan and Ford's animosity prevents them from completing the ritual before Bill finds them.
The image flashed at the end of the theme song appears to be drawn on a page from one of the journals. The paper has various symbols, writing, and other content written on it including a phrase which can be deciphered with Caesar cipher and reads "STAN IS NOT WHAT HE SEEMS."
When Bill summons the Zodiac, it is a bright, glowing blue. A blue light then flickers around the wheel, briefly highlighting each symbol.
Around the circle are ten small images. These images, their placements, and the people or objects they represent include:
- A question mark: Because there is a question mark on Soos's t-shirt, this symbol represents Soos Ramirez.
- An open bag of ice: Represents someone who is cool in the face of danger, and Wendy Corduroy is the one to stand on the symbol in the finale, but it is stated that there is no specific carrier.
- A crescent/Pac-Man shaped symbol: Stan Pines - Stan's fez.
- A pine tree: Dipper Pines - Dipper's hat.
- A pentagram with an eyeball in the center: Gideon Gleeful - the Tent of Telepathy symbol seen on the top of the tent and the back of Gideon's cape.
- A hand with six fingers: Ford Pines - Stanford Pines has 6 fingers on him. There are also six fingers as a symbol in the journals.
- A llama: There is a llama on one of Mabel's sweaters, which is given to Pacifica Northwest in the finale, who later stands upon the wheel.
- A shooting star: Mabel Pines - one of Mabel's sweaters. Also the symbol on Mabel's prison bubble.
- A heart with a stitch in the middle: As seen on his "destiny hoodie", this symbolizes Robbie Valentino.
- A pair of glasses: This represents someone who is a scholar, and while Old Man McGucket is the one to stand on the symbol in the finale, it's stated that it has no specific carrier (person).
- Intro: "Gravity Falls Main Title Theme"
- 119. "Dreamscaperers"
- Originally, the image that was going to appear in the opening was the six fingered hand, but Alex Hirsch decided to replace it because he discovered the TV show Fringe also had a six fingered hand. The idea for the Zodiac was created by Alex in a meeting with Ian Worrel when he was running late for another meeting in an attempt to replace it. The symbols on the wheel were just random symbols from the seven episodes they'd already made by that point, and when the Zodiac became such a phenomenon in the fandom Alex realized he had to write it into the story somehow.
- In Journal 2, on the page with the cipher, the journal has three exclamation points and an arrow pointing to the glasses symbols.
- Stan's symbol was originally crescent shaped, but was changed to a shape resembling Pac-Man in Bottomless Pit. However, the symbol on the zodiac as seen in the theme song remains the same.
- Soos', Robbie's, Mabel’s, and Dipper's symbols have all been seen elsewhere. As they are all on articles of clothing, there are other articles of clothing with the same symbols on them.
- Gideon's symbol bears resemblance to an Elder Sign, an icon in the Cthulhu Mythos described as a form of protection against evil forces.
- Several of the symbols on the zodiac can be seen on the infinity sided dice.
- In the episodes "Dreamscaperers," "Sock Opera," "The Last Mabelcorn," and "Weirdmageddon Part 1" Bill calls Dipper, Mabel, Soos, and Ford by their corresponding symbols on the zodiac (pine tree, shooting star, question mark, and six-fingers/"sixer" respectively).
- In the apocalypse version of the theme song, the image of Bill is ripped out of the page, referencing that Bill is now in the real world.
- Various symbols from the zodiac are on the flag made by the resistance as they plan to take back Gravity Falls, including the six-fingered hand, the shooting star, the pine tree, and the question mark.
- The order of the symbols differs depending on the sighting:
- In the opening and "Dreamscaperers," the order goes question mark, ice bag, crescent, pine tree, pentagram, six-fingered hand, llama, shooting star, heart, glasses.
- On the zodiac that Gideon drew in "The Stanchurian Candidate" the order goes heart, pentagram, question mark, journal, crescent, glasses, llama, ice bag, pine tree, shooting star.
- On the zodiac Ford draws and the order on the cave painting in "Weirdmageddon 3: Take Back The Falls," the order goes crescent, question mark, ice bag, pine tree, glasses, llama, shooting star, pentagram, heart, six-fingered hand.
- On the zodiac Dipper drew in Journal 3, the order goes crescent, question mark, ice bag, pine tree, six-fingered hand, llama, shooting star, pentagram, heart, glasses.
- In this image from Dipper's and Mabel's Guide to Mystery and Nonstop Fun!, every symbol can be seen. (the stitched heart and llama are hard to see, but they're at the bottom of the page. Only the top half of the heart is visible.)
- Despite some of the symbols being metaphoric (e.g. ice bag and glasses), all of them have been physically seen throughout the series.
- The zodiac resembles the Manipura chakra, that is represented as a downward pointing triangle with ten petals.
- It is said that meditating on Manipura will attain the power to save, change or destroy the world.
- The symbols are repeatedly used by the characters:
- The question mark was used by Soos as a weapon in Dreamscaperers, and as the basis of his "Questiony the Question Mark." It also seems to be the main symbol for the Mystery Shack, appearing on many of its merchandise as well as the weather vane and the Mystery Cart.
- Mabel used several shooting star stickers for her scrapbook and her sticktionary. She also used a shooting star shape to tell Stan she drenched his slippers in milk, drew one on Stan's speech, and has one on her prison bubble. It appears on the Weirdmageddon 2 end card.
- The pine tree was mass produced and appears on the Weirdmageddon 3: Take Back The Falls|Weirdmageddon 3 end card.
- Robbie has had his hoodie for ages.
- The pentagram is on the end card of "The Stanchurian Candidate" and most merchandise Gideon makes.
- The ice bag is seen in almost EVERY romantic moment for Wendy.
- The crescent is used on the Royal Order of the Holy Mackerel logo.
- The llama was foreshadowed by Wax Larry King. There was also a llama painting in the Northwest Mansion.
- The cracked glasses technically belong to Ford. McGucket did have cracked glasses before he went insane.
- The six fingered hand is on each journal, and Ford has his own six fingered gloves.