As it turns out, the Extremis hadn't quite finished rewriting Tony's brain. The only potential fix has...consequences.

In a world where Sentinels, people with five heightened senses, bond mentally and spiritually with Guides, people gifted with empathetic powers, Tony Stark has spent thirty-three years overwhelmed by the emotions of those around him and running from his own. Sentinel Steve Rogers wakes up sixty years out of his own time and struggles to deal with the massive amount of new sensory input while trying to find his footing in a New York very different from the one he knew. When they finally find each other, how will their bond change them?

Fusion with Ursula le Guin's planet O. In a world with very different marriage rules, a noble wedding and a magical threat still can't make Merlin, Arthur, Gwen and Morgana talk about their feelings.