Akiri leads the climbers through Murasa's unstable ruin, and when the Skyclave's Roil sends Nahiri over an edge, Akiri and Zareth pull her back to safety. Her willingness to rescue Nahiri makes the lithomancer's later betrayal all the more consequential. They reach the Core, but the escape leaves Akiri, Zareth and Nahiri facing an elemental. Nahiri activates the artifact. Its force removes the threat and kills Zareth, leaving Akiri with evidence that a weapon powerful enough to change the plane can erase the people it is supposed to help. Akiri mourns Zareth as the person she loved, not simply a colleague lost on an expedition.
Akiri takes the Core and refuses to hand it back. Nahiri immobilises her through a hedron, reclaims the artifact and pushes her over the edge. An apology accompanies the act, but does nothing to change it. Akiri's expertise earned her a place on the expedition; her objection makes her expendable.
Nissa saves Akiri from the fall. The survivor tells her what happened and also saves Jace from Nahiri's attack. For the reader, Akiri's testimony changes the question from whether Nahiri might be dangerous to how the others will respond to harm already done. Zareth is not an abstract cost in an argument about the future.