Settled in the story
The last hunt is for anchors, not a single winning duel
The novels settle that the antagonist survives through objects that hold a life outside his body.
This note gives away a resolved story point
By the late novels, defeating the antagonist in a room is not the same as ending him. Objects tether his survival. The plot organizes itself as a search for those anchors and a series of losses when they break.
Readers can still argue about order, cost, and whether every destruction is earned. They cannot honestly call the mechanism an open question. The books answer it.
This journal records that answer in outline only. The scenes themselves stay in the novels.
The other side
A settled mechanism is not a settled feeling. Plenty of readers think the hunt crowds out other endings the earlier books seemed to promise. That is a criticism of structure, and it can live beside the fact of the structure.