The Sibling's increasingly frantic pleas to Navani and Kaladin as Raboniel injects Voidlight into the Sibling in an attempt to Unmake them. At one point, the Sibling begs Kaladin to protect them, saying the Lady of Pains will take their mind, and by the time Navani manages to figure out their emulsifier, the Sibling has grown so weak that their voice was too weak for Navani to hear. The fact that the Sibling is described as having a genderless, child-like voice really doesn't help.
Sibling: SheiskillingmeSheiskillingmeSheiskillingme. Stopitstopit. Sibling:I am cold. They are killing... killing me. I don't... want... to die...
Kaladin killing the Pursuer. He sticks the Pursuer to a wall with Adhesion, then uses Lashings to make the Pursuer's head attracted to the ground. After a few seconds it's ripped off his body.
When Kaladin confronts Raboniel, she threatens that if he kills her when she returns she'll intentionally take the body of the most innocent singer she can find, specifically one with a young daughter.
Ishar's laboratory. Due to his insanity, he's been forcing Radiant spren into physical bodies. This eventually kills them without even leaving a deadeyes behind since their bodies don't follow the physical world's laws. The one who survived the longest only lasted fifteen minutes. The worst affected, though, are Cryptics who die instantly, leaving a twisted body with a mass of black viscera where the head should be.
Just what did Mraize do to his Seon to make them fear him so much? Even Hrathen's Seon was still happy to see him after being shut in a box and treated as a demon. What makes this even worse is that Seons are splinters of Devotion, and do their work because they love their bonded partners unconditionally. They won't accept freedom if offered. And Mraize hurt this poor thing.
Mayalarin's revelation that the spren chose to go through the Recreance creates a very disturbing question; What was so terrible about the Knights Radient existing that the death of hundreds of spren and the tarnishing of the Knights' good name was considered the lesser of two evils?
Taravangian's thoughts on using his dark power to "save everybody" after his ascension as the new Odium.
This is extra disturbing if you're aware of the author's theology; the parallels between this and the Latter-Day Saints' concept of Satan are striking. Context In LDS teachings, when God was originally deciding on a plan for humanity's trial on Earth, Satan proclaimed that he would save everyone by force in a bid to prove his own glory, while Jesus said he would teach them and let them choose for themselves. When Jesus was chosen as the Messiah over him, Satan tried to overthrow God and was banished, and now haunts the Earth tempting people to ruin Jesus' plan and damn humanity out of spite.
During the Epilogue, Hoid works out that "Rayse" isn't acting as he should meaning someone else is now the Shardvessel for Odium. Taravangian responds by destroying Hoid's externally-stored memories, erasing his memory of their conversation and resetting him to the beginning of the chapter. Hoid can tell that something is off when he realises he no longer has Perfect Pitch, but otherwise doesn't seem to realise what just happened to him.