The heart of "Ghostsmith" beats with the complex dynamics of family. Wren's world is turned upside down by the knowledge of her parentage, forcing her to question everything she thought she knew. The reappearance of her twin brother adds another layer of complexity, as she grapples with their shared past and uncertain future. The theme of loyalty versus betrayal runs deep, as Wren must decide where her allegiances lie and who she can truly trust, even when it comes to her own blood.

The pursuit and consequences of power are explored through various characters and their ambitions. The Corpse Queen's ruthless ambition to protect her people, even if it means waging war, highlights the seductive nature of power and the moral compromises it often demands. Wren, caught between opposing sides, represents a different perspective, questioning the price of peace and the lengths one should go to achieve it.

Building upon the foundation laid in "Bonesmith," "Ghostsmith" delves deeper into Wren's evolving abilities as a ghostsmith. She continues to hone her craft, facing new challenges and unlocking hidden depths within herself. This exploration of self-discovery and mastering one's inherent power forms an exciting subplot and directly ties into Wren's journey of determining her own destiny in a world seemingly determined to control her.