[ Frost. Emma Frost. Steve’s memory flashes back to fighting her, then watching Scott tear the Phoenix Force out of her. ]

Fighting against Scott Summers and some of the X-Men. He and four others became possessed by the Phoenix. Eventually the battle became just fighting him. There were casualties, but in the end, the Phoenix was destroyed and the effects of M Day were erased. The mutants came back into the world the way they’d been before.

[ And that, as far as Steve is concerned, had been a victory, though its cost had been so very high. ]