my internet went down as soon as I opened this page.

"i'm wing gaster!"

hmm... what about this one?
R O B I N N O O O O O O O
*I'm Wing Gaster the Royal Scientist!*

ExoDendrite
the wingdings is right. the wingdings do in fact translate to "I LOVE MEN" although in uppercase and not lowercase. a little wrong but, still the same.

Ok so this is pre-written to speak my peace and explain why Gaster's apearance is MysteryMan (looks alone) first being the pattern of mysteryman dissapearing. This one i will admit is a bit of an odd one but every instance of Gaster or Mysteryman in work, be it the posts leading up to Deltarune (gaster) or the cover for the undertale vynl (mystery man) soon dissapearing after some time. [REDACTED] is still on the vynl but mysterman is not. and even in UNDERTALE The mysteryman vanishes if you interact with him. And Entry Number 17 is gone from the main game BUT NOT blocked by the dogcheck, Gaster's patterns tied to him in Undertale and Deltarune seems to include vanishing.
This pattern includes the tarot card that refers to the mysteryman by name as Gaster. Second reason is all the fanart and such of mysteryman gaster, Sans has unkown colored slippers, enough people used pink slipers that Toby used it for merch, same could be for gaster (again, see the card) if Toby has said otherwise take that with a grain of salt, this is Toby Fox we are talking about, he is playing 5D chess and could be pulling our leg.
Yes, there is a potential Toby would allready have sprites ready Mysterman is easy to draw, FURTHERMORE mind you i do not speak for Toby and he could change his mind at any moment. HOWEVER Toby Fox, if you are willing to share this relatively unimportant information of what Gaster looks like go ahead, be my guest. Honestly it would put a lot less stress on everyone regarding this argument. (me included) so long story short Gaster is an egghead in more ways than one. FURTHERMORE i stumbled across the placeholder dialogue translations, now taking toby knows people will over analyze describes mystery man but in the general tone the gaster followers/goner kid address him and their surroundings as the gash/part of your eye that "winds down" mystery man is also known for those cracks(?) on his head. Further enforcing that it could be gaster is intended mystery man as of current DELTARUNE development. (i will continue to update this comment the more information we get) and gaster can also be a nod/reference to UBOA as @TheVengefulRevolvenant mentioned. This over-analysing aside here is my full essay on how mystery man is gaster. Feel free to share this information with all your friends one also does not simply retcon a little under a decade of fanart and fan comics. Personally if I were Toby Fox and gaster had another design I would have shelved it and go through the effort to use this new one. I will be checking back... ok... there we go...

oh, i didnt know @s dont work.

This is the game @inflames14

Isn't this a reference to some other game, with the fun value?

@Dinoshi 64
jus wanted to make sure.

@Sandjaar lmao can't wait for that

@Serif17
it's also worth mentioning that mystery man's fun value is 66 and w.d. gaster's stats in the file are all 6s

@Dinoshi 64
Actual reason I went here wanted to see if it got vandalized with that as a joke or smth lol

I wanna know if anyone will be on this page cuz of VioMarks' tweet lol

Also for anyone wondering, no your screen isn't broken or anything the sprite is not in sheet and never has been, just to let you know

☜☝☝
☠

i dont believe in gaster, i believe in mistery man.

happy halloween

Interesting very very interesting

The Mystery Man Vanish sound it's actually the Gaster theme reversed and accelerated.
It only plays when Mystery Man and the Gaster Follower 2 (the one who canonically holds a piece of Gaster on their hand) disappear. It also plays when the Goner Clam Girl disappears after anouncing the fast approaching arrival of "Suzy".

So that sound it's the main evidence of Mystery Man being Gaster and also their relation with Deltarune, since the Suzy thing was probably made to promote the game.

@Spammyton
Gaster has yet to be so much as MENTIONED is Deltarune
Like yeah he's probably doing some shit but
He is not confirmed to be in Deltarune

ALSO
realized this a few hours ago
Mystery Man is literally a reference to Uboa from Yume Nikki. Wouldn't be the first time Toby's referenced Yume Nikki in his works- Just look at the Earthbound Halloween Hack.