He knows everything, everyone and every event without exception in the Underverse.
These strings are the same as Error 404 strings, but a lot more powerful. These strings can kill or control anyone without any exceptions.
True Omni-Reality Manipulation
He is able to manipulate AU, no matter which one is.
True Omni-4th wall Breaker
He is aware that he is fictional. He is able to have talks to creators and wishes to non-fiction character. He also made a YouTube channelin real life (omniXirus).
He is everywhere all the time in the Underverse, he is also able to break the fourth wall and contact people in real life, however he isn't Omnipresent there and it takes MUCH more focus to do.
True Omni-Virus Manipulation
He can control any virus create the most dangerous viruses; viruses that are more dangerous than Fatal Virus with an absolute ease.
Life and Death Manipulation
This ability allows Omni404 Sans to make one immortal and instantly kill someone with ease. This ability will last as long he wants if he you alive.
Matter of Darkness
He created this matter to make a true evil source, which makes anyone who touches it become evil and about 1500x stronger. It depends on how evil that person is.
He can copy the abilities of his opponent (even for those who have ability that can't be copied), and it'll be much, much stronger.
These blasters are beyond all concepts of power and bypasses any form of defense, these blasters also enables him to immediately erase the code of anything it hits as well as also allowing him rip holes in the fabric of space and time.
He can remain undetected from other Omnipresent beings like 4th Breaker Z!Sans.
He can reset, overwrite, game over and out-code for whole fiction and make them forget or think what he wants. This applies on everyone no matter what the circumstances.
True Omni-State Manipulation
He can control the states of whatever he wants. He can control the states in any game, even the creators who live there.
This ability is a gift that can absorb the powers or the abilities of anyone with no exception as well as gain a ten thousand times boost in power each time he does so.
He can't be overpowered. If there is someone who is stronger than him and they fought each other, Omni404 will increase in power till he becomes stronger. (This does not implies to other omnipotent beings, as they could simply do the same thing.)
The Ability he gained from absorbing Ten No Kami, he can't be controlled or manipulated or any form of magic. However, the only ones who can damage him are creators, such as Toby Fox
That ability makes him able to get any ability that exists on the internet no matter what such ability is.