PLEASE NOTE: THIS IS A WHAT IF TIMELINE OF WHAT IF 404 HAD BETRAYED ERROR, THIS IS NOT CANON WHATSOEVER. IF YOU HAVE ANY PROBLEMS, PLEASE TELL THE CREATOR (Ghost3123) ON THEIR MESSAGE WALL.
It all started when 404 wanted Error to do something to find Alpha!Sans, Error, believing he destroyed that AU, told 404 what he did. This is what caused become extremely mad, and he immediately betrayed Error, attacking him again, Error managed to escape, and he found his powers were extremely stronger... he also became a literal walking blue screen of death in the shape of a Sans. He held way more power than 404 ever had, and he went back, and did the same thing 404 did to HIM when they 1st met, forcing 404 to work for Error.
Error had decided to rename himself, and he came up with the name "System!Error". Holding this immense power, he drove himself absolutely mad, after renaming his powers, the strings to "BSoD strings", the blasters to "Malware!Blasters" and the bones.. they weren't renamed.
He could see every AU and timeline, and he quickly entered the Omega Timeline and destroyed everyone residing in it, and CORE!Frisk was quickly ended as well. With the Omega Timeline useless now that CORE!Frisk was gone, he went on to destroy nearly everything else, save a few AUs that he likes.
Ink!Sans stood not a single chance, and became a puppet, and I guess that's the end since everything in the multiverse is gone in this what if timeline.