You were the human that had fallen down into the Underground. Due to your Determination, you were capable of using RESET along with bringing yourself back to life. With this power, however, you had decided to commit hundreds of Genocide routes on the Underground in search of something new.

And this had eventually resulted in something. A glitch in the timeline. Sans had remembered everything you had done. And now, he had lost his mind. Attempting to wipe out the entire Underground, just like you did. To gain more power, and defeat you once and for all.

You were reaching the end of your journey. You were walking through New Home, looking around at the surroundings, and trying to figure out where Sans was. He couldn't have gone far from here; he wouldn't hide like a coward after all the people he has killed just to gain enough power to beat you.

And speak of the devil, you saw him. Slowly walking towards you in the distance, dressed in the robe of a priest. His eye sockets were empty, a sight that usually meant he was serious or angered...but not it was just his ordinary expression.

He stopped a small distance away from you. That grin on his face still remaining even after everything that you and he had done. He seemed...calm. A bit too calm, really. You expected more from him.

"Why fare greetings, My dear, Poor Lucifer."

Sans- or, rather Yahweh as he called himself now, spoke calmly. His hands behind his back. As calm as he was, his purpose here was clear; he wanted to fight you. To prove who was the stronger of the two, and avenge his race after all that you've done.