Ok. I know that most theorists will be annoyed, but I have to put this out here, just in case. Now, in my last theory project, I said that Gaster IS the goners. Now, Gaster was scattered across time and space, remember? This means that BOTH possible Gaster sprites in Undertale could be Gaster AT THE SAME TIME. Also, the goners are actually just those characters in DELTARUNE. Now, this is just a theory but, what if some of Gaster's pieces POSSESSED all of those goners, but can only possess them if they mention his creation, Deltarune? An example of this is when Clam Girl starts talking about us meeting Susie (she encodes Susie's name as Suzy so that she doesn't actually mention Deltarune) and, when she says "Is fast approaching", she is directly referring to us entering Deltarune, and letting Gaster take hold. Goner Kid (thanks to Undertale, we know that Monster Kid WILL NOT DIE in Deltarune) tells FRISK about a world where THEY don't exist, and that he's terrified at the thought because something bad will happen in Deltarune (probably the Roaring), forcing all of Gaster's followers to escape to Undertale with the help of Gaster (and learning everything about Gaster). This brings me to a Frisk theory. What if FRISK is the one who either, 1: forced the Monsters Underground, 2: CAUSED the war between humans and monsters, or 3: both. Think about it, in Deltarune, Frisk doesn't exist and, in theory, the humans are Underground (the bunker is the Barrier). Another theory is that the humans in Undertale DID have to deal with Dark Worlds but, after using the roaring to help defeat the monsters, they sealed all the fountains because the Titans were a threat to them too, and made sure that nobody made another. Ok, back to Gaster, so if my 'Gaster taking over people' theory is true, then that means that the Vessel that we make in the Goner_Maker is for him to DIRECTLY control without someone else trying to fight against him. Also, remember how there were three "heroes of light"? well, how many Gaster followers are there? Real quick, his name is probably inspired by Dr. Gast from Final Fantasy Vll, his story is, possibly, inspired by Dr. Gast also. Welp, I know this isn't much, but it's all that I could think of for the moment.
Please check the comments below, anantnpapa can tell you more. anantnpapa, thank you. Also, I found out something big. Please copy and paste this link. https://cellydawn.tumblr.com/post/646430143005556736/undertale-meta-deepdive-sans-is-not-a-good I've also added more to this, so please check it out.
