one of my favorite theories is that each of the ruins basic monsters stand for the six souls: whimsun as bravery (the most cowardly at the start, gains courage as whimsalot, with text like "It finally stopped worrying.") loox as justice (its symbol as an eye and bully fits in with the flavor text for yellow in ball game: "Your sure-fire accuracy put an end to the mayhem." vegetoid as kindness (green attack that heals you, the green equipment is apron and frying pan, flavor text in ball game is "Your concern and care for "Ball" led to a delicious victory." migosp as integrity (check says "It seems evil, but it's just with the wrong crowd", ball game says "Hopping and twirling, your original style pulled you through", begins dancing when alone. moldsmal as patience (literally immobile, described as "pensive", "ruminating", "quiet". the sudden appearance of moldbygg mimics ball text saying "You waited, still, for this opportunity, ... then dethroned "Ball" with a sharp attack", and afterward the solution is to leave it be "unhug"). froggit as perseverance (it is flattered or scared even while not understanding, but helps you understand with tutorial text. flavor text in the ball game is "Even when you felt trapped, you took notes and achieved the end", and final froggit is defined by its perfect understanding.)

Pappyrus knows mord than we think because at the end of a pasifist run he says since the royal gard is gone " THIS IS THE WORST ENDING!" ending is the key word

Theory: The reason Sanses clothes randomly change in official art (Such as his footwear switching between white slippers, pink slippers, sneakers and just socks, and his shirt randomly being portrayed as a Skeleton T-Shirt) is because he intentionally changes his clothes every time nobody's looking mid-conversation to annoy them by making his design inconsistent Another theory is that Sans isn't talking about Frisk CAUSING an anomaly in his fight, but that Frisk IS an anomaly, which would explain both their abnormal mass of determination and how they didn't get literally erased from existence from Omega Flowey and moreso Asriel who is LITERALLY OMNIPOTENT-

1 HP sans is a fan theory due to how the code doesn't always fit in line with the narrative like how when u check metta neo they have 9 def but in the code it is -4000 def basically meaning the code isnt 100% undeniable evidence of sans's HP also there is the fact you one shot everything that isn't undying in the genocide run

please make a part two, this is amazing

3:16 the "turn to dust" sound is the same as the one that plays when you spare a monster.

Narrachara is probably one of the best theories as it has been shown that it isn't always the player narrating

Funny how you suddenly started talking in wing dings

Gosh dude you almost killed me with this Gaster sound effect at start bro stop .....((((((

1:23 the hope growing would make sense, because if the human has a larger level of violence, they would probably be less prone to doubt or fear than someone with low lv

3:12 I hate to be the "erm, achtually" guy, but isnt that just the sound that plays when EVERY battle ends, whether you kill or spare a monster?

Have you considered doing a Deltarune theories tierlist too?

I feel like papyrus is secretly knowd everything and toby (in the form of the annoying dog) always tries ro stop him like taking his special attack or straight up taunting him everywhere he goes

If Gaster is Sans´s and Papayrus´s father, then their last name is Gaster, because Gaster is only W.D.Gaster´s last name.

Alright, not sure if this one already exists, but I thought it up awhile ago; it could have plot holes. The theory is that Frisk is Chara reincarnated. The main idea came to me from the idea that Asriel and Chara's stories could mirror each other this way. They both die together and are reborn as different people. This could also make the three main endings a conclusion to their story. The neutral ending is simply Chara and Asriel not finishing unfinished business, not recognizing each other, not really remembering much, and just focusing on the goals of their current lives. Frisk is trying to get out of the underground after being mysteriously drawn to Mount Ebott. Flowey wants to collect the human soul's to become godlike and have fun destroying everyone and everything for his own amusement. The pacifist ending would be Asriel and Chara dealing with unfinished business from their previous lives. They properly meet again and have a final battle where Chara breaks through to Asriel and comforts him because Chara has grown and matured from who they were in their previous life. Asriel and Chara then officially free the monsters like they had originally planned. They then part ways, finally putting their past to rest. And if you include the alarm clock dialogue, Frisk continues to include Flowey in things like Christmas. If this theory were correct, Chara and Asriel's friendship would now also be stronger and healthier than before in this new life. The genocide route is essentially Chara fully remembering their old life while abandoning their current life. They are being brought back to 'life' by remembering everything. Thanks to you having frisk uncharacteristically murdering people, they now believe the point of their reincarnation is to gain EXP, LV, etc. Which basically means in the genocide route instead of it being you, Chara, and Frisk. It's actually just you and Frisk. killing everyone. And as for giving Chara the soul? That's basically giving up control. Chara can now do whatever they want; they let you go on the underground adventure, and what not, but they are the ones fully in control now. Do I believe this theory? Not too much, really; I'm sure there are some errors and plot holes, but it was fun to think about due to it giving Chara's story a bit of a happier conclusion during the pacifist and natural routes.

Theory: Sans comes from Deltarune in some way we will know in the future. Papyrus stated that before Snowdin there was "green grass", implying that they lived on the surface. Also in the machine room there are photos of sans with people you dont know, which could very well be from Deltarune.

I personally enjoy the theory that MEGALOVANIA is the human/player's theme. 1. It plays after Sans attacks first in genocide, and whenever the player attacks first, the respective monster's theme plays. If Sans attacked first, wouldn't the human/player have the theme? 2. MEGALOVANIA is a play on the word megalomania or megalomaniac, something used to describe someone obsessed with power, which perfectly describes the player in Undertale's genocide route! 3. MEGALOVANIA has no apparent leitmotif connections to any other song in Undertale (maybe Bring it in, guys, but that's a stretch). Leitmotifs are used to convey connection to the greater underground and Sans doesn't have it in his boss theme? Why wouldn't he at least have Papyrus's theme in his boss theme since he cares for him so much? It would makw much more sense for bo leitmotif connection to be in the player's theme because, as Sans describes, the higher LV one has, the easier it is to distance yourself. And finally 4. Sans has a battle theme, the unused song, Song That Might Play When You Fight Sans, and heck, Toby had to intricately change MEGALOVANIA when adding it to SSBU alongside Sans's mii costume. Why? Because he needed to connect it to Sans, as it wasn't his theme in the first place. That's all I got, great video!

Not so much a theory but a shower thought - since sans has one HP, will he die if he stubs his toe?

White Spy actually has a crush on Black Spy.

i dont recall where i heard about this theory or where but it was about Chara being the narrator of the story, but i think that was a good one if anyone can find it

You forgot Gaster was destroyed across time and space So they both could be pieces of him broken into 2 skeletons

sans ain't a human, i have 2 reasons why 1. he knows about the sun, because before they got trapped underground the monsters knew about the sun, but papyrus haven't just heard of it, cuz he is kinda... dumb. 2. one of the most popular theorys why sans bleeds, is cuz he has a ketchup bottle in his jacket and shirt

1:35 why would people die of losing hope? But even so, if it's soul-related, then why does Omega Flowey have a health bar? He has no soul, unless that's the combined hope of 6 human souls but I doubt it.

Great video

Undertale au power tier list?

cool vid

good video

Theory is that Frisk soul trait access stand for determination and that the other fellan human souls have there own trait ❤

could you rank the narrachara theory? (the theory that chara narrarates the game)

n u t d e a l e r

Hey kustopia are you going to do a another sans au video?

*INTENSE BREATHING* SCIENCE SANS... UNDERTALE LAST CORRIDOR GIF... GRAHHHH

Chara is the narrator

Ill say mine Hp=hope believable B Frisk is monster D Sans is human -Z terrible W.D gater=sans papyrus C hardly believable Er er is nerd A The six federal crimes are monsters C Sans is ness -Z

Your cool

Its Not a theory i have 1 HP.

6th i cannot believe it

I cool

You better have worn a tin foil hat while you edited this

sans is gaster

Sans is ness fr

I have a theory: everything that is important to Undertale is in the game itself, and Toby Fox didn't expect anyone to make theories about something he never came up with. Crazy, right?

Undertale

no

You will regret not putting like in my comment

My theory is that Frisk is the final enemy in genocide, not Sans. This is because the enemy always goes after the player, and Frisk goes after Sans.

Undertale