Herald of Ruin — Tim Pratt

The enigmatic Carl Sanford is the master of all things occult in Arkham, until a charismatic newcomer threatens to take everything away from him in this dark mystery set in the world of Arkham Horror.

Carl Sanford's mastery of the Silver Twilight Lodge gives him unbridled power and influence, but unforeseen turmoil is coming to Arkham... A new occult curiosity shop in the city, opened by newcomer Randall Tillinghast, draws Sanford's ire, challenging his formerly unrivalled authority. Sanford expects to crush the newcomer like an ant and take what he wants from the wreckage, but Randall Tillinghast isn't quite as humble and harmless as he seems. In possession of an array of magical artifacts, Tillinghast begins to subvert Sanford's reputation in more ways than one, forcing Carl Sanford to call all the monsters and magic at his disposal to stop him. Will it be enough?