The Necromancer's House by Christopher Buehlman

In a secluded house by a tranquil lake, Andrew Ranulf Walker, a reclusive and powerful sorcerer, lives a life of solitude, haunted by his past and the dark magic he wields. His quiet existence is shattered when a malevolent force from his history resurfaces, threatening to unravel the delicate balance he has maintained. As the boundaries between the living and the dead blur, Andrew must confront his own demons and the sinister entities he once sought to control, leading to a gripping battle of wits and wills that tests the limits of his power and humanity.

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