Riven and his knight companions press on toward Castle Moore, only to find new dangers lurking in the shadows. A lost city consumed by dark magic, creatures that refuse to stay dead, and whispers of an ancient monster. The deeper they venture, the more Riven realizes that some threats cannot be outrun.
But danger isn't only found in the wilds. Within the castle walls, Riven must navigate strict rules, skeptical masters, and the stigma of alchemy, a practice long forbidden. When his friend Finn falls gravely ill, Riven is forced to break the rules once more, risking everything to uncover the truth. Something unnatural has taken root within the castle. And if Riven isn't careful, it won't stay hidden for long.