Just finished 3 books, I think Authority is still the scariest one
I dont know if this is a hot or cold take, but after going through Annihilation, Authority and Acceptance, somehow Authority was easily the longest I felt dread and the most pant-shitting moments for me easily, which is funny considering its the book thats outside of Area X for most of it until the end.
The First Expedition footage was FUCKED, despite the fact nothing overtly scary happens the fact the last moment is the expedition members being eerily happy and peaceful after people died (and the implication that the person whos supposed to be dead was sitting with them off camera) was haunting
The thing that fucked me up was reading parts of Annihilations dialogue and conversations in the background randomly which gave me absolute chills, esp since I read it right after Annihilation so I got to immediately notice it
The carpet looking moss-like, and the Southern Reach employees acting strange leading up to the wall changing to flesh when the border expanded was also really good
I dont even need to talk about the Whitby scene. I was dead staring at my book with my mouth open the whole time, easily the most horrific one.