In a world reshaped by catastrophe, Sigma's victory has left humanity teetering on the edge of oblivion, with X defeated and the future seemingly sealed. Dr. Cain's last-ditch gambit, Project Regenesis, offers a desperate path forward—a chance to alter the course of this doomed timeline. Revived for one final struggle, X must confront the forces that destroyed the old world and battle to preserve whatever fragments of human civilization still endure.