The Silence of Unworthy Gods by Andrew Rowe

Upon returning to Valia after his journey to Caelford and the Unclaimed Lands, Corin Cadence is confronted with a familiar foe — his own father. While his strength has vastly increased since his last encounter with Magnus Cadence, Corin knows that he'll need every trick at his disposal — and maybe a few new ones — if he wants to survive a duel with his father intact.

While Corin struggles with his family, his friends must face a second year at Lorian Heights with new classes, familiar but new chancellor, and deadly new enemies both on and off the campus. But school itself is the least of their worries. As the year progresses, the nation of Valia faces new travails at the emergence of a mysterious faction targeting attuned commoners and foreigners. Casualties mount as Corin's allies seek to unmask the leadership of this deadly order — and discover a threat that they cannot hope to face and emerge unscathed.

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The Silence of Unworthy Gods is the fourth book in the Arcane Ascension series, a progression fantasy epic that mixes dungeon crawling and magical school content. This book also references events from the Weapons & Wielders series up to Book 3, a connected series that takes place several years earlier with some overlapping cast members.