I read through the section where Saubon dies so quickly I didn't even catch the call back to TWP and Mengedda. Wow, how fucking utterly horrifying is that?
Maybe the darkest and most horrifying moment in this entire series. Wow.
When Kellhus first excavated the infernal device before it had been adequately described I wondered if it was like a fossilized-in-amber Titirga. Gotta be down there somewhere, neh?

When Saccarees pondered contacting Kellhus but didn't I felt like it was some foreshadowing of disaster harkening back to the disaster in the previous book. But then we never heard what came of the confrontation and he's just back there with Proyas at the end? Strange.
What about Wreoleth early in the book? Was it some Topos and the band of Ordealmen that went there became possessed in a way?