We have UT Red & Yellow, but why not... ¡UndeTale RainBow!
just a pixelart of Undertale
I really liked the UT Red & Yellow mod, I hope that the following fangames (and the webcomic) have the same popularity as UTY and that they are canonized in the UT fandom.
(It would also be great if this mod could access the routes that the previous humans were on, since in the mod they could be visited in a very limited way)
NOTE: none of the humans were made by me, all credits to their respective creators