A strange dream sends Finn on a mission to help Billy stop the Lich once and for all.
Tropes
- The Bad Guy Wins: The episode ends with the Lich successfully tricking Finn into opening a portal to the multiverse, which he escapes into.
- Batman Gambit: Finn breaks the Enchiridion in order to keep it out of the Lich's hands, but it turns out this is how one activated the portal, and the Lich was counting on Finn destroying the Enchiridion in an effort to stop his plan.
- Body Surf: It turns out The Lich killed Billy and hijacked his body.
- Briar Patching: The Lich tricks Finn into breaking open the Enchiridion and opening the portal by making him think he didn't want the Enchiridion to be destroyed.
- Dead Person Impersonation: The Lich has killed Billy and now wears his skin, confirmed in the next episode.
- Dreaming of Things to Come: Finn's dream at the start causes him to seek out Billy, so it may be part of the Lich's plan. However, it also contains hints of the Lich having already killed and impersonated Billy.
- Enhance Button: When the Enchiridion shows a hologram map of the multiverse, Jake commands it to "Enhance," causing it to zoom in on the universe, planet, and exact location of Jake holding the book. Then it zooms in on the hologram and does the same thing. Repeatedly.. It gives Jake a headache.
- Evil Plan: A rather successful one, ever since possessing the snail, the Lich has been trying to get the book and manipulate Finn into using it for him.
- Face Doodling: Finn does this to the Ice King after stealing the gems from his crown.
- Foreshadowing: There are several clues in the episode that hint that “Billy” is actually the Lich in disguise.
- During Finn's dream, when Billy is laughing he switches to the Lich in one frame then back. Though this was removed in the Hulu version of the episode.
- After Finn tells him about his dream, Billy asks him if he is ready to help him save the world from the Lich. However, Finn only said that the snail killed him and never said anything about the Lich, something that Finn and Jake fail to notice.
- Billy never physically touched the gems, and refused when Finn tried to hand one to Billy.
- Billy was unable to speak to Jake while he was using his head as a gem holder. It’s been established in "Mortal Folly" that the Lich cannot communicate with anyone wearing a magical gem on their head.
- Billy had said he found the Enchiridion in the mouth of a bear, but the viewers already know back in the episode "In Your Footsteps" that the bear in question gave it to the Lich-possessed Snail.
- Genuine Human Hide: It turns out the Lich is wearing Billy’s skin as a disguise after killing him.
- Hero-Worshipper: Deconstructed with Finn. Finn is shown to still be one for Billy, openly trying to mimic him as they go after the Gems of Power. The Lich however exploits this to trick him into stealing the Gems of Power in the first place by suggesting "Billy" wants to banish The Lich using them and the Enchiridion, Finn ignoring the signs something wasn't right due to having that much faith in Billy. It reaches the point that Finn actually wrestles with Princess Bubblegum when she won't willingly give up her Gem, and ignores the Gumball Guardian declaring Billy an "evil presence" in favor of focusing on the fact Billy was blasted, only relenting when seeing for himself The Lich was using Billy as a skinsuit. Finn's hero worship of Billy not only makes him easily manipulated, but it demonstrates his willingness to go along with what would normally be suspect behavior and oppose his friends if he thinks it will help Billy.
- Info Dump: A rather extreme example. After finding The Enchiridion in the possession of Billy, Finn flips the sword on the cover, activating a hologram of a fellow named Booko, who gives a Motor Mouthed explanation that the Enchiridion has a secret power when combined with the Gems of Power in the crowns of all Ooo royalty.
Booko: What you see here is a map of the Multiverse. It shows all known dimensions and the links between each of them. This is the dimension that currently contains the universe in which we currently reside [...] At the center of the Multiverse is a dimension called the Time Room, believed to be the quasi-coporeal dwelling place of the almighty Prismo! The Time Room is a single dimension that exists outside of time. The Time Room produces the Time Waves that are experienced by other dimensions. Some dimensions have permanent links that allow travel to and fro. Others become linked temporally by naturally forming wormholes, and others can become linked artificially by magical portals, torn open by items of great power. Once the last gem is inserted into the Enchiridion, it will have the power to create a portal to any dimension in the Multiverse. An activated portal creates a time dilation in which either end of the portal experiences a temporal synchronization allowing for the safe passage of particles through a non-local region of space-time!
- Killed Off for Real: It turns out Billy has been killed by The Lich.
- Manipulative Bastard: The Lich is shown to be this, when he gets Finn to destroy the Enchiridion for him.
- Mind Screw: The episode ends with Finn and Jake following the Lich into the portal... then it abruptly cuts to what appears to be an alternate version of Finn with oddly-shaped eyes, a prominent nose, and a mechanical arm.
- Nice Job Breaking It, Hero: In his haste to keep the Enchiridion out of the Lich's hands, Finn destroys it... which is how one activates the interdimensional portal, and is playing right into the Lich's hands.
- Omnicidal Maniac: The Lich wants to destroy the entire multiverse.
- Pie-Eyed: Finn's briefly go like this when he sees what happens to the Enchiridion once the jewels of power are placed within.
- Playing with Syringes: When Finn tries to get Princess Bubblegum's tiara, she is experimenting on a group of miniature Candy People, including cutting their limbs off with scissors and transplanting them or reattaching them in different places. While they don't appear to be in pain or frightened by this, the sequence is disturbing enough that it was censored by some channels.
- Real Dreams are Weirder: Finn has a troubling prophetic dream about Billy and the Lich, but then Jake tries to reassure Finn by telling him about his own weird dreams.
Jake: I dreamed I was in kindergarten again, but I had really big feet, and was also the teacher.
- The Reveal: Billy is really The Lich, who has killed and impersonated him.
- Running Gag: Apparently the Enchiridion doesn't want LSP's jewel, not even the forces that would destroy the multiverse want anything to do with her.
- Sacrificial Lion: Billy is the first major sympathetic character to die in the show.
- Sequel Episode: To "Mortal Recoil" and the consequences of "In Your Footsteps"
- Shout-Out:
- The tapestry on the wall in Finn's dream is similar to the final one in the famous medieval Belgian series The Hunt of the Unicorn.
- Booko's narration and the simple holographic visuals are similar to the treatment of the excerpts from the Guide in the TV version of The Hitchhiker's Guide to the Galaxy (1981).
- Two-Faced: When the Gumball Guardian shoots "Billy", the left side of his face is burned off revealing the face of the Lich.
- Well-Intentioned Extremist: Deconstructed with Finn and Jake. After Finn's premonition dream prompts them to see "Billy" and he says they need to get the Gems of Power, the two proceed to aid him in stealing them from across Ooo no questions asked, only expressing concern when Finn finds "Billy" has the Enchiridion, upon which he explains his "plan" to banish The Lich using them. This prompts them to storm the Candy Kingdom and steal the Gem in Princess Bubblegum's crown when she refuses to hand it over, Finn even wrestling with her until she accidentally cuts him. To Finn and Jake, helping Billy banish The Lich is too important... which is exactly what The Lich counted on, knowing they'd go along with whatever "Billy" asked of them if it was in the name of the "greater good". Even if they were well-intentioned, the extremes they're willing to go to is what made The Lich see them as the perfect pawns for manipulating.
- Wham Episode: Billy is revealed to have died, with the Lich wearing his skin to gain the trust of Finn and Jake. Once they gather all the gems he needs, he activates the interdimensional portal with the intent of destroying the entire multiverse.
- Wham Line:
- During the episode's end, we cut a a different looking Finn before saying this line, revealing that this an alternate version on him.
Finn: Coming Mom!
- Just as Finn is about to give Billy the Enchiridion, Bubblegum shouts at him on who he is really giving the book to.
Bubblegum: Finn stop! That's not Billy! It's The Lich!
- What Happened to the Mouse?: While Billy is confirmed to have been killed and the snail and old lady would reappear later, its never established what became of the bear after The Lich killed Billy.
