Fortune of the Forgotten Extra

He transmigrated into a webnovel as a background character. Not the hero. Not the villain. Not even the comic relief side character with three lines and a memorable death. A nameless extra in one crowd scene who the author never thought about again. Kael finds this darkly funny. He was a civil engineer and a veteran in his previous life. He has survived worse positions than irrelevance. He has nine years before Concordia Academy's story begins. Nine years to prepare, to build, to quietly improve every broken system this world has been too comfortable with to fix. He has knowledge of the novel's plot, a luck manipulation ability that everyone considers a joke, and an engineering brain that a medieval fantasy world has absolutely no framework for. He has a plan. Stay invisible. Fix things from the shadows. Let the genius mage with the legendary artifact handle the dramatic moments. What he does not have is a plan for the secret organization that decides a nameless commoner building impossible machines is more dangerous than any prophecy. For the brewing war that threatens to swallow everything he has quietly built. For the god being assembled in the dark beneath his feet. Or for the moment he stops treating the people around him as characters in someone else's story and starts treating them as his. That part was not in the novel.