He was a most extraordinary storyteller—he always had been—and for a time Esmenet found herself lost in the Battle of Anwurat and its wrenching intricacies.
This solves the narration problem of the battle on the Sempsis.
Presumably Achamian, described in the chapter headers as writing the Compendium, is our third person neutral narrator. This makes it odd we would see such a detailed breakdown. How could he have seen so many fields, even if he had been present? Wasn't he trapped by the Spires while the battle took place? But we know from his transcript of Kellhus speaking that Esmi has an excellent memory, and now we know that she heard the clearest version from Kellhus. Probably some of what we were told in the last chapter was simply colorful inference.
