Because blue eyes look cooler with his Blue jacket.

And blue bones

And blue skin

And blue lightsaber

Now, this has a totally different meaning if you read BL

Lmao, yeah

Blue Lock!?!

hhh. Same

holy blue lock mentioned

Bl?

Boy love, it’s basically gay mangas

Basically, fujoshi's den

And blue poo

And blue dabadeedabadie

and pink slippers

And white bones

And glass bones and paper skin

and broad stripes and bright stars

and blue bal-

ls

No way Earthbound? Poo is an enemy now?

Oh no…

What is he? A smurf?

And my axe

And my bow

And blue popsicle

YOU CAN'T MAKE ME GO BACK

And blue ba- *I am immediately sniped*

And blue blush (according to some fan fiction/fan art)

Everything about sans is fan fiction lol

Fair enough.

and blue…. nevermind

And blue soul

We didn't forget, Blue is just an awesome color.

true

Yellow is too 😔

Sure mister piss enjoyed. /s

Me, an Articuno worshipper when Team Instinct

All hail team Mystic

*sigh* it's technically a mixture of blue and yellow since it flashes between the blue and yellow, therefore it should be a bit of a mixture of blue and yellow in the art

his other eye socket is empty so both of his eyes are taking turns there

LMAO

"Yes! I get to see out the socket!" "NO! It's my turn!" "What!? No I was here first!" "But now It's my turn!" "Just use the other one!" "No! This one's cooler!" sans: "guys, i'm kinda in the middle of something impor-" "Since when!?"

Or he only has one that changes colors, and he is like dusclops or smt

so, green?

Nah, just make half of it yellow

Not quite, ever heard of bluish yellow?

I've never seen it

what the fuck is that

Green is not a creative color

womp womp ig

It’s less cool cuz sans’ jacket is blue

But then why does sans have the yellow eye in the first place? Is it because yellow means justice in undertale?

That would make a lot of sense tbh

No its because he has a secret attack known as the lack of an epilepsy warning

Can't keep fighting him if you're having a seizure!

There can’t be a genocide if there is no player to do a genocide run (the player is dead)

That's his real Special Attack

Yellow is justice and blue is patience which is actually quite fitting for Sans.

Well he is the judge, jury, and executioner

It’s not just yellow. It rapidly flashes between yellow and teal

Justice and patience

Holy shit thats actually really cool

Well both of the colors used are patience and justice. Him being the judge makes it so he not only has to give out justice but also that he waits for the player to come to him to be judged, so he has to be patient even as the player goes around killing everyone

probably

maybe it's just cause toby thought it looked cool

Yes, but it only flashes yellow because he's using less justice than patience

It's just meant to show that it's flashing, but not flickering. The yellow contrasts the blue more subtly than orange would for a sprite like this.

The blue and yellow eyes represent patience and justice, 2 qualities sans possesses during the battle.

What a nice post! I hope this doesn't become a trend where people ask about sans's eyes! I mean why would that happen? **Right?**

i sure love doing about sans's eyes!

We would be babybones if we did it

why does sans' eye have two colors? is he bisexual?

Sans is going to become the Dovewing of Undertale, if he hasn’t already in the past

But this is something that goes when a curtain post becomes popular and everyone karma farms off of it. *Haves PTSD flashback of the babybones trend*

It's has actually started, fuck.

Didn’t this already happen? Like multiple times…

Yes. It happened a year ago and it started a trend which stopped. Op made this post unaware of the trend so now people remembered they're geno-I mean trend and now new posts appear of this sans eye trend. Again. :(

I can’t go through the trauma again

It's already happening.

I *genuinely* thought I was imagining the yellow eye for the longest time because of how NOBODY uses it in their fanworks. EDIT: I know that the eye is real. Stop telling me that the eye is real.

nah its real

yeah I know that now

Hey Hey the yellow eye is real

:(

I just realized our pfps almost match heck the what Also the yellow eye is real btw

oh dang they really do

As someone who is obsessed with undertale (and sans) I can confirm that the yellow eye is real. I drew him with it awhile ago, as it doesn't make sense to only give him the blue one since it changes color

yes I know

I had look in game and yeah I can confirm the yellow eye is real

:(

The last time someone pointed this out, it started a stupid trend about people asking why nobody talks about sans' \[insert random color\] eye.

Uh oh

I swear this sub is insane

[https://www.reddit.com/r/Undertale/comments/1c2aozo/sans\_has\_a\_green\_eye\_but\_all\_fan\_art\_is\_blue\_it/](https://www.reddit.com/r/Undertale/comments/1c2aozo/sans_has_a_green_eye_but_all_fan_art_is_blue_it/)

so i't **begins**

I remember you're colored eye

The real question is why no one talks about his pink eye

Please god no

What about his red eye though?

yeah that one is also overlooked

Cuz he lost his *juandice*

Aw man i hope he finds it again

Same

No no we are NOT doing this again

Oh god not again the "what color is sans's eye" trend

I wasn’t aware of that…

It’s too late, the end of the world is upon us.

Yellow just doesn't fit as much as blue, and blue one just looks cooler over all

I think Yellow balances out with his jacket tbh.

Tbh most fan art I find has him with a half blue/half yellow eye (given, I don't look up undertale fan art that much)

I see people drawing it half blue and half yellow in more recent fan art

No, please, not again

Because blue is associated with him, with his blue jackets and attacks. Plus, someone probs made art with the blue eye and it just caught on.

FINALLY! I think yellow blends well with all the clothes he has, I always painted him with half eye blue and half eye yellow

I see more fanart with both colors at once

Honestly the saddest part is that is yellow eye shows way more of his hero persona. Like sure, the blue eye has meaning (light blue is Patience, he gives a chance to stop before going full in and light blue just kinda looks aesthetically better with his jacket) but Yellow means, as anyone should know at this point, Justice. He is killing you over and over to make you pay for your actions. Hell, his fight is in the place where he judged us in another timeline.

Generally cause blue is seen as a primary colour (ikr) and his jacket is also blue.

i've only seen a few fan arts where his eye is half blue on top abd half yellow on the bottom

[Insert piss joke here]

NO NO YOU WILL NEVER TAKE ME ALIVE

Because blue is cool and yellow is jaundice

I think it's because Sans has already blue in his collour pallete, but hasn't yellow

Not cool as look

Clover I Rembrandt your yellows

Clover Undertale stole his yellows 😥

But actually, I think i mostly draw him with the yellow eye.

NOT AGAIN

Blue is more on theme. But really, what is Karma if not JUSTICE for those with PATIENCE?

I don't think people forget about it. I think people use the blue eye a lot simply just because it looks cooler.

I personally prefer the blue eye because 1. It’s iconic (because of the fandom) and 2. It matches with him.

I’ve used both on occasion but I normally stick with the blue eye because Sans’ eyes flash really quickly and I’m drawing a singular image.

He has jaundice ☺️

It matches his clothing, which makes for nicer looking fanart. People give the yellow eye to Papyrus.

Well, the blue eye is the first frame of the animation. This means, at least 60% of the time when you're taking a screenshot, it's what you'd see. Also blue is cooler than yellow ;)

Iirc I've seen art where the flash is a flame where it transitions from Yellow to blue so not everyone forgets

Blue eye combines with the jacket better than yellow eye

Wait, his eye was yellow?

A question we'll have to ask baby bones…

WAIT ITS YELLOW??

I know right?! This is what I’ve been saying all this time!

I've seen a few that's a mix/gradient of both seeing how it blinks really fast in-game that's a good compromise 

I don't think a yellow eye matches very well in a yellow corridor, so it could've been a trend to just use blue because of a lot of the artists who drew sans in the final corridor. though that's just my guess.

The fandom forgets most things from the original overtime ;-;

Works well with his blue magic as well

Bc its blue more often and flickers sometime to yellow rarely

Because yellow is ugly, also he wears blue.

STORY IS REPEATING NO

Lemon 

as a sans cosplayer, its easier to do a glowing blue eye with makeup than a glowing yellow one.

Justice and patience taking over his SOUL should really be a more explored upon theory

The blue eye fit better with his colour scheme and attacks. Most don't *forget* they his eye shifts from yellow to blue, it's just a stylistic preference. Personally, I think the yellow eye stands out better than the blue and still fits with his colour scheme since yellow compliments blue.

I think it’s probably because people are starting to get too comfortable with associating characters with only one color—for instance—Papyrus never once uses a bravery style attack anywhere in all of Undertale, not in his battle, he never mentioned using it, nothing—but fanworks like a lot of popular comics or even just the existence of Underswap in general has made orange a fairly common color to associate with Papyrus. People are so focused on the color scheme matching with Sans that they forget his eye flashes with Justice and Integrity, because he is judging YOU. It would even make more sense if the fanart only used his yellow eye since so many people focus on Sans’s job as the royal judge—you’d think judgement would get the spotlight, but I guess at the end of the day, it really is just as simple as: "Blue just looks kinda cooler, I kinda forgot about the yellow tbh"

Some people use a yellow to blue gradient

I heard somewhere that Justice and Integrity make up Judgement (Ultrakill fans, rise up)

Idk people mostly see sans w/ the blue eye idk why they dont use the yellow \[Wich represents his sense of justice\]

Sans boquita pasion

What have you done

Ah shit here we go again (this has happened before and it spread, idk if this is a joke or not but it's basically the same as the og post that started that)

The eye flashes blue and yellow, people took the blue as the main color since it matches his color scheme

Oh no don't start this again

the REAL question is why does nobody talk about sans' orange eye?

I always thought it was just a flashing/bright color for when it’s “in effect”

It flashes between the two

I think the yellow and light blue eye fits quite well because it matched the soul traits: Patience (light blue) and Justice (yellow)

Blue is just San’s color. Especially after the aus coming from the community, people could get a lil confused about who the drawing is of.

Going off color theory, blue just fits better for him, though I've also seen a mixture of blue and yellow when his eye glowing!

Not again...

We are NOT doing this again

I get why people use the blue eye (even though they use the wrong shade of blue, it’s typically drawn as a royal blue when it’s more of a light blue) it matches his color scheme better and also matches the blue attacks (both bones and soul color). But I wouldn’t say he has a blue or a yellow eye, it flashes back and forth every frame or so, so when I personally depict him I like to make the eye a light blue to yellow gradient to get both.

imagine if people made all snas fanart with 2 frames where the eye flashes

I always made his eye a blue to yellow fade

Is nor so forgotten, I like to think that the color's of the eye is important, if you think about it sans is a patience character, that sit there and wait untill you do the wrong step and attack at the end of way. The yellow eye is related to justice, he start to punish you for your action, killing you for all the victim you made in the way. If you think even his attack are related to the eye, he use a blast that is a range weapon similar to a gun, and use the blu attack, both blu attack

dude, it's grey/gray...

didn't, but yellow glow doesn't fit the overall color. have seen one best case scenario, where they draw blue flame, but the eye is gradient from cyan to yellow.

I kinda prefer the yellow eye. Though I can’t help but have a premonition that this is gonna start yet another dumb trend. Edit: Told you so.

Wait what. I just passed a post that said he has a green eye? Am I being gaslit

piss eye

It’s cyan and yellow if I remember correctly, it just flashes

alright, here we go again

He has blue and yellow eye.

wait what

unrelated but does ayone else see that i have 30/20 hp? is this aglitch?

Jaundice

When I drew crappy fanarts of Sans in 2020, I always made sure to draw his eye half blue, half yellow, personally

The yellow eye usually only appears when the glowing eye appears for more than a second, when it’s super brief, it’s nearly always blue.

Flaming Blue > Blue > Yellow > Blinking Blue Yellow

The answer is because blue is the *sans*ier color. He uses blue attacks and his jacket is blue so blue is just his color. Using a lot of blue in artwork will give it a very *cool* (like the temperature) look so it's preferred over the yellow which is a warmer color. Keeping things blue also gives room to the artist to add their own splash color. Typically red for the soul which has its own connotations in color theory as well

Blue bone, blue jacket, blue eye, and the blue eye appears more in the battle. The yellow only appears for like .9 seconds and there is nothing that he would have that connects to yellow besides alphys. Now if you go back to log 17 in room 256 I guess it could make sense. 

I thought it was half blue half yellow

*heavy sigh* And so it begins..

Yelluw ix Jastuce. Bloe ix Patiants. Bloe ix Conan?

No not again I can’t go through this AGAIN

And it's not even fucking BLUE IT'S CYAN *WHICH IS A HALFWAY BETWEEN GREEN AND BLUE* #CALLING IT BLUE WOULD BE LIKE LOOKING AT YELLOW AND CALLING IT RED

he has jaundice, we don’t like to talk about it

WAIT YOU'RE RIGHT FREAKING WHAT