The Second Artificer by Kenan Buchanan

Thaddeus Blackwell opened a door he was never meant to find—and the world paid for it. Thrown across fractured worlds, Thaddeus is pulled into a reality shaped by magic, factions, and at the center of it all, The Lich… waiting to escape. To set the world right, Thaddeus must follow the path of the First Artificer—a myth, a warning, a man who may not be ahead of him at all. As the Rift tightens and timelines repeat, Thaddeus faces a final, impossible inheritance, because the Rift is not a wound; it’s a mirror, and Thaddeus was never the savior of this story. He was its most necessary mistake.