Fans of the cult-classic series, Gravity Falls, are more than familiar with the epic series finale event known as Weirdmageddon–but one thing fans may not know (as it wasn’t fully explored until after the show was finished) is that the scariest element of the odd apocalyptic event wasn’t what they thought.

Weirdmageddon was the name of the apocalyptic event caused by the unfathomably powerful Bill Cipher–a being from the second dimension who burned his entire reality to the ground and sought to rule over the third dimension. Before Bill gained full access to humanity’s reality (and after he decimated his original one), Bill was trapped in the dreamscape and could only influence people through their shared dream space. Bill only found his way into the mortal realm through interdimensional cracks between intersecting realities after Grunkle Ford (and by extension, Grunkle Stan) tore through those cosmic barriers with a multiversal portal–then, when the one thing that reinforced those cracked barriers was finally destroyed, the villain was set loose on Gravity Falls as a living god of chaos. Thankfully, Dipper, Mabel, Grunkle Ford, and Grunkle Stan were able to outsmart Bill and defeat him before he took over the whole planet–and eventually, the entire universe.

Related: Gravity Falls’ Grunkle Stan Has a Dark History with Marvel’s Stan Lee

Gravity Falls: Lost Legends–written by series creator Alex Hirsch with art by Joe Pitt, Ian Worrel, Asaf Hanuka, Dana Terrace, Jacob Chabot, Jim Campbell, Kyle Smeallie, Meredith Gran, Mike Holmes, Priscilla Tang, Serina Hernandez, Stephanie Ramirez, and Valerie Halla–is a graphic novel telling the stories of Gravity Falls that weren’t told during the course of the animated series. In the story titled “Don’t Dimension It” (which takes place immediately following Weirdmageddon), Dipper, Mabel, Grunkle Stan, and Grunkle Ford are walking through the woods, closing lingering portals Bill created that led to hellish dimensions. During this mission, Mabel is grabbed by a demonic figure and falls through the portal, becoming lost in the random horrors that awaited her on the other side–and she could have been trapped there forever.

Bill Cipher Wasn’t the Scariest Part of Gravity Falls’ Weirdmageddon, His Portals Were

Gravity Falls' Mabel being pulled through a portal.

Given Bill Cipher’s malevolent nature mixed with his unlimited power (which he uses to do horrible things like conjure a living severed head that screams in eternal agony, or create furniture made of pulsing, twitching human flesh and bone), it makes sense that he’d be considered the scariest part of the armageddon that he brought about. However, this comic reveals that Bill himself wasn’t the most terrifying part of the whole thing–the portals he opened were, and the reason is that they operate independent of Bill.

Bill Cipher can conjure any horrible thing he wants from thin air, but those things disappear when he is vanquished. Beating Bill undid most of the weird damage he caused, meaning all the heroes had to do was defeat him, and they’d have pretty much saved Gravity Falls in one fell swoop. The portals, on the other hand, had to be dealt with one at a time, and each of them led to demonic dimensions that contained horrors on par with whatever Bill could think of–proving that Bill Cipher, the obvious choice for being the scariest element of Gravity Falls’ Weirdmageddon, wasn’t the most terrifying aspect after all.

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