Kang!
He had many titles: The Supreme, The Ruler, The Conqueror, The One Who Remains...
His real name was Nathaniel Richards, and he was a scientist from the 31st century.
He discovered that above his world, there were also multiple universes.
At that very moment, other versions of themselves had also realized this fact.
Then they invented high technology to travel through the multiverse and timelines, thereby communicating with each other.
In the beginning it was a peaceful exchange of goods and needs, where they shared technology and knowledge with each other, and the universes learned from each other's strengths to make up for their own weaknesses.
However,
not every Kang was so harmless; many Kangs had the goal of standing at the peak of the world and looking down upon all living beings.
So war broke out.
Kangs from all timelines were fighting for the survival of their own worlds while destroying other universes.
That was the end of the world,
the end of all worlds.
And so,
the Kang standing behind the Time Variance Authority appeared.
Kang the One Who Remains!
The person who slaughtered all Kangs and successfully remained behind.
As long as The One Who Remains lived, only three Kangs existed across the multiverse and the timelines!
Past, present, and future.
Then the past, present, and future formed a closed loop, and this loop was the so-called Sacred Timeline.
Because once a branch appeared on a timeline, Kang the One Who Remains would prune that branch.
A variant of Kang would be born on every single branch!
The abilities mastered by those variants were almost identical, and they were extremely good at causing trouble.
"Loki, why don't you just die? You have to be so persistent and make everyone live such exhausting lives."
Kang the One