Warning: Unmarked Undertale spoilers below.
The plot is centered around W.D. Gaster, as indicated by the blog's name. Other major characters who aren't canon to Undertale include Gaster's wife Lucida and his sibling Harlow Garamond. It has gone through several complete Story Arcs- some of these are modified parts of Undertale's canon story, while some began by the whim of a "magic anon", and one was a crossover arc. The comic has ended with a written summary partway through an arc taking place after the canon story, based on a Soulless Pacifist Ending, but it has been Un-Cancelled and currently on-going—although it no longer accepts asks, instead acting as a standard webcomic. This YouTube channel is making the comic's official dub; it also does AFAC's.
Provides examples of:
- Adult Fear: Think about the situation of Sans and Papyrus from Gaster's point of view. Your wife died several years ago and you've just been left unable to take care of your sons, one of whom is only six years old, leaving them basically orphaned and you unable to do anything about it. Sure, you're alive to watch them grow up, but you can't do anything to help them, even when one of them is showing signs of depression. He's been stuck in this position for at least twelve years.
- Ambiguous Gender: Subverted for Frisk and Chara. While initially going by gender-neutral pronouns, Chara is eventually revealed to be male and Frisk is eventually revealed to be female.
- And Here He Comes Now: When prompted by the askers to think of happy times with her children, Lucida recalls how small Sans was as a baby. When she starts recalling how small Papyrus was, the skeleton himself pops into the scene seemingly out of nowhere.
- Another Dimension: What Gaster theorizes the portal in the Voidcrossed arc leads to.
- Back from the Dead: Lucida is resurrected in Voidcrossed, and Gaster and Asriel are restored to normal life at the end of the Pacifist arc. Chara returns via possessing Frisk's body.
- Back Story Horror: It's been revealed that HG was an agent for the Royal Guard during the war between humans and monsters, and they killed hundreds of humans.
- Been There, Shaped History: Harlow-Garamond is an unwitting example. It turns out that their human hunting in disguise during the war gave birth to a legend that ultimately led to the creation of the holiday now called Harloween. They are less than thrilled when they learn this in present day.
- Body Horror: During the True Lab arc, in spades. The imposter Gaster starts melting when Frisk realizes that it isn't the real one, and the imposter Harlow displays just how terrifying their jawless appearance can be.
- Creepy Good: Gaster himself. He's a shapeshifting skeleton with a badly mangled/deformed face who was Dummied Out of existence itself, and a kind, polite, dorky scientist who deeply loves his wife and children.
- Crossover: The Voidcrossed arc was a crossover with Ask Frisk and Company. The mod has stated that she plans for the blog to have more crossovers with other Undertale ask blogs.
- Death by Childbirth: Gaster's wife, Lucida, after giving birth to Papyrus, came down with an illness caused by magical overexertion. The illness usually isn't fatal, taking away only one or two HP, but Lucida only had 1 HP.
- Inciting Incident: Gaster's fall into the CORE.
- Also, to a degree, the Magical Anon's ask that sets Gaster free from the void for a limited time.
- Interface Screw: For a long time, all of Gaster's text was displayed in Wingdings font, effectively making him The Unintelligible to readers without looking at the captions. Beginning with the Voidcrossed arc, this was subverted when the comic opted to adopt AFAC's system (display text in a different font over the Wingdings).
- During the Pacifist Arc, the blog's URL changed several times.
- Leitmotif: 'Everything Stays' for Lucida, or at least as much as this trope can be used in a webcomic.
- Secret Keeper: Asriel knows that Chara is controlling Frisk's body.
- The Soulless: After the events of Voidcrossed, Lucida's revived, but with one difference: her soul is broken, leaving her unable to feel joy. She recovers over the course of the next two arcs.
- Sudden Downer Ending: The Pacifist Arc ends with Asriel defeated as he is in a typical in-game fashion, but in a twist he discovers his soul survived within the Heart Locket and no longer has to revert to a soulless flower. Further still, a side effect from the final battle has returned both Gaster and Lucida back to normal, and all three are able to join the protagonists and Harlow in living on the surface. ...Then Chara opens his eyes, revealing the Pacifist Run depicted for what it truly is—a Soulless one.
- Un-Cancelled: Partway through the Genocide arc, the comic was ended, but Rei later resumed it.
- "Where Are They Now?" Epilogue: The epilogue given before the comic was Un-Cancelled.