Abhorsen: La novena puerta

The combination of bells, necromancy, and the boundary between life and death feels so distinctive. I wonder what the author drew from when creating this system.

The tension really ramped up, especially during the confrontation with the Charter. How did others interpret the importance of balancing power and morality here?

Every detail, from the geography to the different types of magic, felt so well thought out. Curious whether this universe was mapped out entirely or evolved during writing.