Extus draws the Blood Avatar through the Snarl and fills the Hall of Oracles with destruction. Rowan seizes raw power from the vortex and overwhelms Extus, but the energy begins to consume her as quickly as it empowers her. Will reaches her before rage turns unlimited power into another catastrophe. Their reconciliation starts with survival, not ceremony.
A Mage Tower lesson gives Will the answer: the Blood Avatar is a summoned being, so it can be intercepted rather than beaten head-on. His control spell cannot overcome Extus alone. Rowan stops trying to merge her lightning with Will's ice exactly as they once did and instead feeds her strength into his precise construction. The combination succeeds because they accept their differences.
The Avatar crushes Extus and is dragged back into the Snarl, but its last stroke takes Will's lower right leg. Five weeks later he walks with an ice-and-steel prosthesis and the twins choose to remain students. Liliana stays too, setting aside her resurrection research to teach under her true name. Strixhaven survives, and every survivor carries a lesson the school could never schedule.