Recently I saw a comment of someone genuinely not knowing why people were so obsessed with Undertale character, Dr. W.D. Gaster, in regards to Deltarune. The replies were people either agreeing and not knowing the significance of the character on a meta level, neither canon nor fanon, or people being just as floored as I am that others are missing the obvious hints. Then I realized. Undertale’s popularity reached a peak around 2016. That was years ago now. Dr. Gaster was a big point of interest and all the evidence of his existence and significance is basically buried on fan wikis and ancient Tumblr posts which may or may not even exist anymore. If you played Undertale in isolation right now, it’s likely you will just never find out about any of this. You either need to be able to decompile the game, or you just need the internet where other people can do that more easily and find out all about it there. In contrast, I knew who Dr. Gaster was before I even played the game. That’s how big of a deal he was seen as in the early months of the fandom. That has waned over time because… there is no conclusion to Dr. Gaster. He existed in the world of Undertale, now he doesn’t. We can’t even be sure 100% of what he even looks like. So, here’s a video explaining who the hell Dr. W.D. Gaster is and why he’s painfully significant to Deltarune. I’m going to try to list things as objectively as humanly possible, as much Gaster information and content has since been overrun by fanon since you kind of had to make things up if you wanted to make fan content for him. I will try to make it clear when I am either speculating or repeating popular fan theories. Okay. Here we go. There is a hidden character in Undertale named Dr. W.D. Gaster. He was Asgore’s former royal scientist before Dr. Alphys. You can find out about him through hidden NPCs that can be rarely seen during regular gameplay, and can be manipulated into appearing through simple edits of easily accessible files, using an otherwise useless mechanic, the “fun value.” Fun value is a random number generated at the start of a playthrough, and depending on what number you get, many things will possibly occur. Here’s a handy chart I found on the Undertale wiki. These gray monochrome NPCs will tell you a story about how Dr. Gaster was a brilliant scientist who created the Core in Hotland, but then “fell into his creation.” It can be inferred that the creation is the Core, since it was mentioned shortly after the comment about him making it, but the Gaster Followers’ dialogue can be just vague enough to make me doubt literally anything. After he “fell into his creation,” Gaster seemed to have vanished, implied to have been erased from existence entirely, probably even everyone’s memory. He was said to be “shattered across time and space.” The very hidden log known as Entry Number 17 can be found by easily editing files to Room 264. This room is labeled “room_gaster” in the files of the game. The entry is written entirely in all caps WingDings font. It can therefore be easily assumed that the W.D. stands for WingDings, thus it can be assumed that Dr. WingDings Gaster might also be a skeleton, considering the theme of naming skeletons after fonts, and them speaking their text boxes in those fonts. It’s also entirely possible that Gaster is just the Aster font with a G tacked on. He gets two! In Entry Number 17, once translated into actual words, reads what seems to be the middle of a conversation about an experiment. That's my Gaster voice, I hope you like it. Remember the phrases “VERY, VERY INTERESTING” and “DARKER YET DARKER.” They are important for our purposes. Please also remember this very distinct sound that plays while Entry 17 is being read. [garbage noise] There are also apparently battle stats for Gaster hidden in the files of the game, every stat, defense and attack, even the money payout upon defeat, is just a series of sixes. If the fun value is at 66, either by way of pure 1 in 1000 chance luck or by file editing, there is a 10% chance you can find a gray door in Waterfall that leads to a small room with THIS sprite. This sprite is called “mystery man.” Because of the fun value needing to be set at 66 and the battle stats being all sixes, this is the commonly assumed appearance of Gaster. This is technically speculation, but I feel it would be genuinely weird if this didn’t turn out to be him, considering the number 6 motif. This sprite can easily be seen as resembling a distorted cartoon skeleton, perfectly in line with the somewhat unorthodox skull shapes of Papyrus and especially Sans. The distortion also lines up with being “not whole” since Gaster was shattered across time and space. He has no nose, no legs, no visible arms, nothing that can even be interpreted as fingers, and generally looks a little melted. Him being melted and goopy is basically universally accepted fanon, but is extremely possible in canon, if he did, in fact, fall into the Core. You know, the thing harvesting searing geothermal energy. But... speculation. I want to quickly say my own little theory here. So, making it clear right now what I'm about to say is theory. I really do think that this "mystery man" sprite... HAS to be Dr. Gaster. Not just because of the sixes, but because... seemingly every fun value event is somehow related to Gaster. Other events include Sans prank calling you. Sans is implied to be somehow connected to Gaster. Alphys accidentally calls you when she’s trying to order pizza. Alphys is brought up a few times by the Followers, and shares Gaster’s position as a royal scientist. The sound test room... is only notable for containing Gaster’s Theme. Four of the events are Gaster Followers. And there’s one involving the mascot, ICE-E, who is only brought up once in all of Undertale, by Sans, but is a prominent corporate mascot in the world of Deltarune. The misfits here seem to be the Wrong Number Song, and for a few years, Clam Girl. Clam Girl is an NPC in Waterfall who talks about her neighbor’s daughter, “Suzy.” This now adds up in retrospect, but even more than that, when the Switch port came out, if you got Clam Girl by sheer dumb luck, and talked to her after you beat final boss Asriel, she goes grayscale and says the time you will meet Suzy is fast approaching. Deltarune Chapter 1 came out a little over a month later. The phone call is the most vague, but they ask if they can talk to someone whose name starts with a G. You’d think Gaster, but hey, it could be Grilly, it could be Gerson, it could be... G. Spamton!! Oh my god, I don’t know. I don’t think this G was put here for no good reason though. However, I can’t tell you with any amount of certainty what I think it stands for. I think Gaster might be the explanation here, but that might be confirmation bias. Theory over, back to the Mystery Man sprite: The only other sprite that could possibly be him appears in a debug room, which is just for developer testing, and therefore may have no actual significance on actual canon. This could have possibly just been for making sure the WingDings font was working properly, but I am not going to rule this sprite out. Something also notable, but doesn't tell us too much is that the skulls Sans uses to shoot lasers when he Megalovanias you are called Gaster Blasters in the files. This does at least tell us that Sans has got to have something to do with Gaster. Sans is also seemingly good friends with Alphys, but no one really knew that. and they seemed to have worked on a mysterious mystery machine together. Uh, not that one. Because the handwriting is said to be very bad on the blueprints, and it's said several times that Alphys' handwriting is very bad. As mentioned before, there’s a hidden sound room in Snowdin activated by fun value, that includes “Gaster’s Theme.” A simple creepy melody. Once it is playing, it cannot be stopped. Then it says, "Thank you for the feedback!" If you try to put in the name Gaster at the beginning of either Undertale or Deltarune game immediately crashes the second you put in the last letter. You don't even hit "enter," it just crashes. Now... What does any of that Undertale bullshit have to do with Deltarune? Everything. This has everything to do with Deltarune. You know how Undertale characters feature prominently in Deltarune? I'm halfway convinced that Gaster is actually a Deltarune character that somehow weaseled his way into Undertale. Now, in a tweet regarding Chapter 2, Toby Fox has said hat he's glad Deltarune is being seen as its own thing rather than just purely in its relation to Undertale. Which, it should be! It is its own game. Most of the main characters are unique to Deltarune, and it has its own separate story and world But even if Deltarune is its own thing, its own universe where no plots points from Undertale ever carry over… Deltarune can’t be divorced from Undertale. Undertale is context for things that happen in Deltarune. Whenever you download it anywhere, it always is sure to say it’s a game for “people who have finished Undertale.” Many characters from Undertale reappear here, some even being entirely unchanged. Hi, Sans! Many just have a change of costume and career, and are otherwise the same person. There are many jokes that fall completely flat if you’re not familiar with Undertale. “Who’s Alphys?” A joke that hammers in that this is an alternate universe. A book so you don’t forget the name of “Hots Fireguy.” That one’s really obscure if you only finished Undertale once. Asriel has a picture of a flower on his wall. The plots in the graveyard are the Amalgamates. The first time we meet Deltarune Asgore directly mirrors when we met him in Undertale. Spamton NEO is literally using Mettaton NEO’s body, and the song “The Power of NEO” plays exactly how it was presented in Undertale within Spamton NEO’s battle theme. ["The Power of NEO"] ["BIG SHOT" with "The Power of NEO"'s melody playing the backgroud] “NEO is known for its high defense!” Comparisons to Undertale are inevitable, and obviously Toby Fox knows this, he is making them himself. I think the desire is more to not think of Deltarune as just “Undertale 2” or assuming it’s in the same universe and that the pacifist or murder routes are going to affect it at all. So, I’m not saying that Deltarune and Undertale are somehow secretly directly linked and this story is all going to come back around to Undertale. I don’t want it to. I like Deltarune for being Deltarune. It is its own story, but doing so riddled with references to the game that is its direct predecessor. Hell, I don’t even necessarily think that the Gaster in Undertale is the Gaster in Deltarune, but I think it’s reasonable to assume we can use the information from Undertale and apply it here. The association with the number 6, and the similar way his dialogue gets formatted are very basic things that would probably get carried over to a different version of the character. With that said, Gaster has an absolutely undeniable presence in Deltarune, more so than he ever was in Undertale. This actually predates the game, Deltarune itself. Deltarune.com has existed since, I believe 2015, three years before Chapter 1 came out, and the year Undertale itself came out. On it was a dark image called “him.png” that, if brightened, would show the text, in all caps WingDings font, reading: “THIS NEXT EXPERIMENT SEEMS VERY VERY INTERESTING.” Then it changed to another message in all caps WingDings, describing the plot of Deltarune: "THREE HEROES APPEARED TO BANISH THE ANGELS HEAVEN" "NYUHUHU" It’s Dr. Gaster, I don't know why I'd need to go on, because of how obviously Gaster is god of the Deltaverse, but I will. Also of note that the image is called “him.png,” there is a file related to Gaster in Undertale called "him," and the song that plays in the intro of Chapter 1 is called “Another Him.” Another Gaster. Two of them. Then there were a series of surprise tweets on the Undertale twitter on October 30th, 2018. These tweets are written in all caps and odd spacing, very reminiscent of Entry 17. “WELCOME. HAVE YOU BEEN LOOKING FOR ME? HOW WONDERFUL. I HAVE BEEN LOOKING FOR YOU AS WELL. I HAVE SOMETHING I WANT TO SHOW YOU. SOMETHING I THINK YOU WILL FIND VERY VERY INTERESTING.” I'll admit, when “VERY VERY INTERESTING” popped up in these tweets, I just about had a goddamn heart attack. Then Chapter 1 actually comes out. At its beginning, we have most likely the same ominous voice as was on Twitter narrating to us. I can't believe Twitter was actually useful for something. “Another Him” playing. There's no hint bombs like "VERY, VERY INTERESTING" in this opening, but it is using all caps and the same distinct spacing. I assume the reason it's not in WingDings is because we need to read it. It wouldn't be very Big Shot of Gaster to make the seizure warning indecipherable. So, if you wanna be a smartass and say "But he's not speaking in WingDings!" Shut up. When this style of speaking is dropped, and it’s written in proper capitalization- Theory time. - there is actually a compelling theory involving the Japanese translation that might suggest that the original Fallen Child, default name Chara, from Undertale, who was already a similarly ominous presence, has taken over and hijacked the character creator. Assigning you to Kris, a teenager not unlike Chara. Of course, since there are so many similarities between the two characters, you could also assume that this might have been Kris themself, but that’s going into Vague Unprovable Theory territory. Also I’m not saying this is the same Chara, it’s very possible there is a separate Chara in Deltarune. However, I like to think it’s the same one and they’re dead now and venturing between universes and Gaster has to babysit his boss’ kid for eternity. Anyway! Finally, we get into the actual game. Let me stress that all of that I just cited was before the actual game begins. In the actual game, the main plot is about Kris and Susie, two teenagers that discover a “Dark World” in the school supply closet. Come Chapter 2, there appear to be multiple Dark Worlds, with new ones being created. What might this remind us of? “The darkness keeps growing,” “The shadows cutting deeper,” “Photon readings: negative.” This closet is emitting darkness as if it had the same properties as light. I think photon readings would have to be negative in order to do that. Also, if you look at Deltarune's information, at least when it was just Chapter 1, I haven’t checked since, the version is labeled 6.6.6. I don't know why Gaster is Satan, just go with it. Wait. ...Theory. Gaster fell into the Core, and Deltarune is about an angel. Gaster’s a fallen angel. Anyway! When you beat the so-har-it-literally-took-me-three-years-to-beat-him bonus boss, Jevil, he either spouts of something about the Knight, yet another vague ominous entity. Or if you FIGHT him, he foreshadows Chapter 2's Queen. Jevil is off, he’s too giggly for comfort, doesn’t always use correct words or grammar, is absolutely obsessed with chaos, and seems to be aware that he’s in a game. Also I love him and he'll never know that. Once you beat him, you can go to plush toy cat shopkeeper, "Shawm," who has officially ruined how I read the word “seam.” They will explain Jevil’s deal. He met someone strange, someone who no one really knows who it was. After that, Jevil went coconuts and started babbling about how everything was just a game. Nothing here is damning evidence until Seam says that because of this, their view of this world has grown “darker, yet darker.” What an oddly specific way of phrasing that, Seam! When Chapter 2 came around, the mystery narrator that we’re presuming is Gaster, returned to Twitter. No telling quotes here, but I want to point out how funny I find it that Gaster Narrator thanks us for our patience in “THESE DIFFICULT TIMES.” Not even being shattered across time and space keeps you safe from COVID. Gaster was out of work for like three months, it was terrible. Chapter 2 is pretty straightforward at the start, even if you're, you know, murdering. When we get to the bonus boss of this chapter in the normal route, Spamton and his NEO form, things become vague and ominous very quickly. After you beat Spamton NEO, the personifications of internet advertisements, the Addisons, all go to the garbage dump where Spamton had been living, and when talking to them one by one, Spamton’s sad backstory is revealed. He was an Addison like them. He still is, really. He still has the same permanent smile, the same tasteful v-neck sweater, and the same nose. It took me far too long to notice their similarities and I need to validate that by explaining it like it's new information. He was very unlucky and never got attention, until he suddenly started spending all of his time on the phone with someone. No one knows who it was. But suddenly Spamton was awfully popular, to the point where all the other Addisons stopped hanging out with him because they felt unneeded. I'd like to point out that this game made me feel bad for ads. Jesus Christ... Eventually whoever was calling suddenly disappeared. While not perfectly fitting puzzle pieces, I will say, Gaster seems to have a real talent for suddenly disappearing from existence. But more than that is the final Addison says that he went to check on Spamton after Spamton got evicted from Queen's mansion. They didn't find Spamton, but found his phone with the receiver off the hook. When the Addison tried to see who Spamton had been talking to, they say they heard "nothing but garbage noise." What makes that relevant is that if you try to use Kris' cell phone in the Dark World, it plays the exact sound effect as that plays in Entry 17, a sound effect that isn't used at all anywhere else in either game in this state, [garbage noise] [the same garbage noise] and describes this sound as "nothing but garbage noise." Hmm! It's pretty much accepted that Jevil and Spamton were driven mad by the same mysterious force, but for a long time it wasn't terribly clear who that was. Many people were convinced it was Gaster, as he's the most vague ominous unnamed presence we have. He can tell them the true nature of the world they live in, because he more than anyone seems to be aware of how much this is a video game. But many thought it was The Knight, also mysterious and vague. No one knew what the Knight's deal was, so it also seemed reasonable to assume. Some people thought they were the same person. That Gaster is The Knight. However, the end of Chapter 2 gave us a very compelling candidate for Knight, so Knight Gaster may be less likely. But with this "garbage noise" point, that cannot be a coincidence. Toby Fox is the writer, he approves everything that goes into the game, he knew what this was going to be implying. So, that is the undeniable surreal breadcrumb trail of W.D. Gaster. I want to go over some things that could be damning evidence, but might also just be a coincidence. One thing is Gaster Theme. Undertale and Deltarune are known to reuse tunes. Usually for very relevant reasons, like when characters have connections. Or maybe it’s just the main theme of the game and sneaks its way into half the tracks. Gaster’s Theme might show up a few times in Undertale, and seems like it shows up a lot more in Deltarune. I can’t be entirely sure, because Gaster's Theme is very simple. It's four creepy sounding notes strung together, and then again at a different pitch. [Gaster's Theme] Some of the instances of what sounds like Gaster's Theme might actually not be it, but rather because there's a simple melody that might share two notes with Gaster's Theme. This might be on purpose it’s so short and so simple, actively and intentionally causing you to hear it everywhere. Like, it sort of sounds like it’s playing very low in the bass of Rouxls Kaard's theme, but it's hard to completely make out. ["Rouxls Kaard"] There's also an instance where it might be playing in the songs "Circus" and “The World Revolving,” two songs associated with Jevil. Because of the extremely possible connection Jevil may have to Gaster, I am not ruling this out at all, but it's not an immediately obvious example. ["The Circus"] ["The World Revolving"] You can see how this could get tricky. Gaster’s Theme does, however, play very clearly in the background melody for Card Castle. I will not let that go, that is what's playing. ["Card Castle"] And it has to be playing in the song at the very beginning where the guy who sounds like he's Gaster is speaking to us, it's just missing a note in the middle. ["Another Him"] I'm not going to pretend that ridiculously talented musician and known leitmotif enthusiast, Toby Fox, didn't know what tune he was using so clearly for the main melody. There is a lot of fan speculation and headcanons around Gaster. He is the perfect combination of vague mystery and just enough information to work with. There's a very popular assumption is that Dr. Gaster is Sans and Papyrus' father. This headcanon is not at all unfounded, even if there is no real implication of it in even the most buried information. The reasons people think this is due to things like Sans' Gaster Blasters. They are part of his own unique monster magic, but are distinctly named after a another character. You know, like he inherited them or something. There is also the vague possibility that Papyrus also has these, that they were part of his special attack that the Annoying Dog ruined. This is inferred from when you and Papyrus hangout if you spare him after doing the Kill Everyone route up to that point. [slowed down version of "Snowdin Town"] If you look in his box of bones, he says it's his special attack that could have "blasted" you had he used it. Too vague to prove anything, but notable enough as to not dismiss it entirely. There's also the fact that it's rare to see multiple types of the same prominently featured monsters that aren't related or somehow connected. Every boss monster is related. Toriel and Asgore were married and Asriel is their son. Outside of them, there are no other goats. Napstablook, Mad Dummy, the Ruins Dummy, and Mettaton are the only ghosts and are all said to be cousins. It's a very sense-making assumption that all the skeletons are related to each other. Father is commonly assumed, but it isn't our only option. He could be a third brother, or a cousin. This is going sound very "tinfoil hat," but there's a song found in the files of the Undertale demo called "Grandpa Semi." Likely referring to Semi Serif, a font. Grandpa Semi seems to be a genuinely scrapped character rather than a fake scrapped one like Gaster. More proof of this is that if you mess with the concept art and notes Toby posted to his Twitter, you can see the writing on the back bleeding through, and "Grandpa Semi" is clearly written. This was a character at some point early on. It is very possible that this character may have morphed into Gaster over the course of development. So, Gaster might be their grandfather. "Can your grandfather do this?!" "Hey! Hoo! Ha! Hey!" "Aaw..." Sadly, I have no smoking gun for the skeleton family claims, but there is one more thing that is… very, very interesting. The vaguest most unprovable thing I want to bring up just because it's so simultaneously mysterious and hilarious is on Toby's aforementioned notes, on the notes for Papyrus is says "has a brother named comic sans and a [blank] named [blank]" I had the thought that maybe this was just blacked out because it's early info that didn't go anywhere and he doesn't want to confuse anyone with thrown out concept art. But then why didn't he black out the whole thing? Why leave the "and a" and "named" very clearly in there. Toby knew exactly what he was doing when he posted this.
