Game Theory: The Many Sides of W.D. Gaster EXPOSED! (Undertale)

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Part 1 - Who is W.D. Gaster?! ►►
I Fight Undertale's Flowey in Minecraft! ► 

Since Undertale's release, one question has plagued the fan base - Just who is W. D. Gaster? I'm diving further into the mystery behind this bizarre and obscure character.

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Twitter: @MatPatGT

THANKS to Edward, Thomas, Lee, and Ryder for the amazing editing on this video!

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ARSO Dahomie
Sooo, Sans isn't Ness? BUTT HOLD ON! If determination in excessive amounts melts monsters and even fuses two into one, and if Gaster fell into his creation that we believe is the determination extractor (takes away determination), does it have the opposite effect and split him from one into two?

This would explain and support what mat's saying about Gaster splitting into Sans and Papyrus, but if we remember what Mat said in his "Sans is Ness" theory about Ness losing his organic matter and becoming Sans and a starman becoming Papyrus, what if "organic matter" included human determination? What if somehow, Gaster in his split pieces combined with what was left of Ness and the starman and fused all the determination together again creating two into one again (Sans and Papyrus)? What if Sans is the amalgaman (or whatever it's called) of Ness and Gaster?

Would kinda explain how Ness got into the Undertale timeline... BBBUUT HAAY, that's just a theory, a GAME THEORY!
(all credit for that line goes to MatPat...)
Evelia Ramirez
( . )o( . )
SpinDash Gaming
You are amazing matpat
she is been pos
by sans
Whose to say that gaster is the one who speaks in hands
Garalithic Perez
So... Gaster is a FUSION!?
Basil Baldwin
J!nx the fox
but ever thought. gaster could be the dad? but thats. not comfirmed. he look like a skeleton and looks like the brothers. or people take a little thing way too seriously gaster. is probably just so random guy who happens to be an undertale that's pretty much probably just it. but i like gaster
death note
y u do dis
Undyne The Undying
Sorry MatPat but you remind me of Walter Jr. from breaking bad
I still would like to say that we always will have your back Matpat.
Tony Vuong
I liked your video
DBZ & Games With Van
Magellan Beaulieu
4:21 4:30 wtf
W.D Gaster sans and papyrus
your take on things is AMAZING. I can't wait to explain this to my boyfriend. we are both obsessed with this game.
W.D Gaster sans and papyrus
there is actually another quote from riverperson about gaster
W.D Gaster sans and papyrus
doctor who!!! yasss
W.D Gaster sans and papyrus
you are an amazing person. Wow. THANKS SO MUCH! I UNDERSTAND STILL SO MUCH!!
Ryan Beal
Sans & Alphys didn't write the lab entries, but instead Alphys and the Nabstablook.
First of all, wouldn't some of the lab entries be written in comic sans if it was Sans (Ik, so it's not that obvious that Sans wrote the entries, but...) and the Nabstablook at least speaks in all lowercase, too. Also, Alphys & Nabstablook have an obvious connection. In the secret pink Nabstablook's house, the journal entries reveal that the Nabstablook and Alphys have a connection through Nabstablook's cousin, or Mettaton. Alphys built Mettaton his body so she/he could become a performer. Through all of this, the Nabstablook & Alphys must know each other. Sans and Alphys- not so much.
I would write more, but I think this is the gist of it...
Max Jonsson
gaster made pap and sans whit his hands but a good vidieo!!!
Scott Stokes
you the boss mat
Sunset The Cartoon Lover
Mark Wolverton
Ridiculously long comment follows. So long, I had to put the second half in a reply. I apologize in advance. ^u^;

So... This is definitely a step in the right direction since you last Undertale theory. At least this time, you're using evidence that's all present within Undertale itself, rather than going into a completely different game series. However, I think you missed a few small details that unfortunately have a big impact of your theory's validity. Specifically, I think you made a few logical leaps without enough evidence, and in some places it seemed like your claim was shaping your interpretation of your evidence, rather than that evidence shaping your claim. I'm trying my best to be constructive here, so if anyone decides to reply to me, please do the same and tell me anywhere you think I made a mistake. Let's go through some of you a few flaws I found in the video, point by point.

5:20 - "Widely accepted" does not mean "credible evidence." I, for one, think you're right for the wrong reasons here. We can be pretty sure that Entry Number 17 was written by a Royal Scientist, since it talks about science-y stuff like photon readings and experiments, and the only two in-game characters who seem to be doing anything related to science are Alphys, the current Royal Scientist, and Sans, who, thanks to the dialogue in the True Pacifist ending you point out later, we know has some secret connection to Alphys. And we can be pretty sure it isn't written by Alphys, because, unlike the rest of the entries (yes, ALL the rest of the entries. I'll get to that one when you do.), it's written in a non-standard font. The only other two characters who speak in fonts different from all the others are both skeletons, which Gaster might be, but Alphys is almost certainly not. And if Sans was the one writing it, it would've been written in either Comic Sans or the game's default font, and would probably be written in lowercase. Therefore, we can assume that the only other one who could've written the entry is the Dr. Gaster, the previous Royal Scientist. And since we now know that Gaster has spoken in Wingdings, and the only other characters with unique fonts are skeletons who are named after the fonts they speak, we can deduce that Gaster is a skeleton whose first two initials stand for his signature font, Wingdings. You formed your argument the other way around, using the "widely accepted" evidence that he's named after Wingdings to prove that he wrote the Wingdings entry and is connected to the other two unique-font characters, rather than worrying about how your evidence became so widely accepted in the first place.

7:13 - Why are we looking at the Mystery Man sprite? I thought we agreed in the last episode that that sprite is in no way confirmed to be Gaster. At the very least, you should've talked about why you think that that sprite is indeed Gaster, such as the correlation between Gaster's in-code stats and the FUN value needed to see the sprite. But that evidence is far from conclusive, seeing as how the Gaster Followers suggest that he was shattered into multiple pieces, yet the Mystery Man appears to have a fully intact body. Also, the rhyming Gaster Follower says that it's holding a head that it claims is a piece of Gaster, but the Mystery Man certainly looks like it has at least one of those. Possibly two if you turn it upside down. So yeah, more evidence is needed here if you want to convince me.

7:29 - Your original claim was that Gaster tested the DT-Extractor on himself. Determination seems to make Monsters' bodies sticky, and helps them hold together in cases when they otherwise wouldn't, as can be observed in the Amalgamates (whose bodies are permanently stuck together) and Undyne the Undying (whose body reforms after partially turning to dust). But using the DT-Extractor on himself would've extracted what little Determination his Monster SOUL had. And if too much Determination holds magical bodies together, then I don't think it's too much of a leap to assume that not having enough Determination would prevent the body from holding together. AND, since Determination is the power that gave Flowey and all the humans who fell into the Underground, including the Player, the ability to turn back time and "continue" reality from a past "save point," it would at least somewhat make sense that Gaster losing a large amount of Determination would scatter his existence across different Save Files with different FUN values. Your earlier claim actually makes quite a bit of sense. So why are you changing it up here by saying that Gaster is an Amalgamate? If he had really melted himself, why would his fate differ so much from the Monsters that Alphys melted? And what would that have to do with Gaster "falling into his creation?"

9:03 - Since when did we know that Gaster was a skeleton? Like I said earlier, I do believe that Gaster is a skeleton, but I provided evidence as to why I believe that. I expect you to be better about doing the same.

9:13 - Why are you looking at the "aster" separately from the "G?" After all, his name isn't "W.D.G. Aster." In fact, two of the three Gaster Followers refer to the previous Royal Scientist as just "Dr. Gaster," not even mentioning the "W.D.." And since Gaster very likely speaks in Wingdings, but has never been confirmed to speak in Aster, I think it's a lot more likely that only skeleton's first names are determined by their fonts, and that "Gaster" is just an unrelated last name.

Youtube seems to be having trouble posting a comment this long. The second part of my response to the video will be in a reply.
The random gaming girl
MatPat, when you said Gaster was Sans I was shocked....

Guess you could say I was FLABBER-GASTERED
Miss L
cyber hug Thank you for this vid
Yuuki Asuna-san
8:42 "Keep an open mind"
Does it ring a bell?
U know what's weird? Your channel is as old as exploding tnts channel
MatPat is one of the smartest people I have ever seen. the math he does would kill my brain. Not to mention he manages to show you stuff you wouldn't be able to put together even if YOU could access alternate timelines and correspond with yourself.
Fatality Gamer
Support Matpat! #supportmatpat
HoveringLamb15 Plays
I dont know if this is true, but didn't at the end of the game Sans said "Were forgetting someone" What if was Gaster
Lisa Clements
sans is two people!!!
PacMan/ Ghosts
👈🏼👌🏿👉🏼👈🏼🖐☝🏼️💣💧❄️❄️👈🏼✡❄️💣💣 lol
Ellen Ochabillo
i almost cried and we will always be here matt
Zoey Zimmerman
Zoey Zimmerman
💣✌❄🏱✌❄ ✋🕯💣 ☝☹✌👎 ❄☟✌❄ ✡⚐🕆☼ 💧❄✋☹☹ 💣✌😐✋☠☝ ❄☟☜💧☜ 👎⚐☠🕯❄ ☝✋✞☜ 🕆🏱 ✏
gabriel porter
My theory about Gaster is that, from the Sans is Ness video, is that Ness and Co. went to a different time to defeat Guigas, and never left. So the Scientist, Dr. Andonuts rebuilt the machine as quick as he could to find the kids, and like Ness, suffered the consequences of organic matter. But he accidently traveled to the same location(time?) as Ness, and ended up finding each other. As they changed their names to "fit in" more in the Underground, Dr. Andonuts Changed his name to W.D. Gaster, and Ness - Sans. Gaster eventually became the Royal Scientist in his Skeletal form, and Sans became the Royal Assistant. Gaster Ended up fixing his "gizmo" to try and get the Co. that was left in another time, and Sans waited for their return, and he did come back, but not "Completly". Then the Events of the True Lab happened, and Sans Volunteered for an injection of xX_DETERMINATION_Xx in an attempt to retrieve and rebuild Gaster from the timelines he was scattered into. BUT PLOT TWIST! he failed. And until The first Human fell, he was spending almost all the time he had trying to get the Time-Machine back into "Proper Working Order", but ended up giving up when he met Frisk, and he was probably right to, as he wasn't the person to do it. Gaster made it, and only Gaster could fix it. But Hey, I'm not the Theorist here, am I? Pls find this Mat
May Kun
Lol others say gaster is sans father or who created sans
Blonde Guyz
Hold up... it's been 6 YEARS???? Wow... time flies fast....
Issac The Issac
Also when you kill Syren, only the head dies
clockwork pyro
This give me nightmares
kuba ratajski
I feel sad for you
Morfin De
"I know that we are living in the age, where people are afraid to be wrong, and so..."
Plz, follow ur example and do that for video about Samurais, Knights and Vikings. Because research, witch is always be a bright side of ur chanel is definitelly unsufficient there, so u kinda making disinformation, and 3 popular utubers replied u with videos about it. To remain silent about it is kinda.... like to say "I don't give a f**k, about my auditory, witch I mislead" Bad attitude, srsl.
Michelle Krause
wait so if you are saying the blueprints are wingdings then you debunked a part of your sans theory
Unknownable H
Wait, the lower case fonts could be Napstablook :/ no offense, it's a good theory
Doctor Who references are life!
Yeah, when I was trying to fight Undyne in a genocide run, she melted. I thought she would turn into Undyne the Undying.
Johnny Holiday
Zj Ang
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