Inception of The Lich

So this happened in the most original D&D adventure I have come up with to date. At one point I wrote of a wizard, trapped in a labyrinth of the mind of a Minotaur due to his evil time schemes. The wizard realized he could get further, and find/generate more complexity in the maze by taking certain paths. He left a note indicating he would see how far he could take that, perhaps there would be a way out by causing the maze to generate too many forks at once.

The party found a dust covered note, and so much time had passed that the wizard king's court had become undead. The party found the Minotaur (Minoas) and reminded him of who he was. They used their music box (which possessed a specific kind of time travel, limited in scope and effect, varying each time, seemingly for a purpose) and they knew it had the chance of drawing the animated guardians of Amand'Laith, the time traveling city (the wizard king's city in the future, after he had become The Lich, bent on controlling all of space and time) (For reference here, the labyrinth was a separate timeline, Minoas' domain exclusively, as he could shape reality with his mind, and at one point traveled the stars, but since had sequestered himself feeling that reality held no challenge anymore). The guardians came, and Minoas responded by duplicating himself for every shield guardian that showed, one shotting each with his axe.

The party just had to fight the animated armors, the easier guardians, that came out first. They knew they could stop the cycle by finding the one with the time loop device embedded inside it, but Minoas had other plans: exhaust the resources of a city that could craft and send shield guardians from any point in their timeline back through the same portal. So he expanded the maze in effect near infinitely, in unexpected dimensions, so the shield guardians would keep appearing.

That was when they heard a primal scream from somewhere in the labyrinth, seemingly all throughout it. The wizard king had been searching for maximum complexity (represented by the greatest number of forks leaving a room he could find). He had been doing this for quite a time, and I didn't even place a number in my mind how far he might have gotten. When Minoas split the maze, his essence was shattered and split across the edges of the whole thing, turning him into The Lich, of an entirely different making.