1 The void

As the darkness consumed him, a long supressed laughter could finally be heard. He'd had a good run, and with his dying breath he had convinced them that most of the multiverse had been destroyed. He slowly began to play around with the nothingness while waiting for his inevitable demise.

He had already mastered the 8 commonly known dimensions, but had now discovered the 0th dimension, void. It was a paradoxical dimension that, being the embodiment of absence, by definition could not exist, yet could not avoid existing. True absence involves the absence of absence, it's how the multiverse you're reading about came to be(oversimplified).

These thoughts raced through his mind, and he understood how to keep a good prank going. By keeping time paused for longer than initially planned, he might understand the void. By understanding the void, he might be able to leave it, and reenter the universes.

If time moved at a normal pace, his speculations and experiments would take a week. Such a long period of time-manipulation would cause problems for those not proficient in the time dimension(separate from the four dimensions of time), but it was no difficult feat for someone who had both great mastery due to centuries of practice, and a soul at what he'd named "the grand nope stage".