Reservation X"" begins, and a new world for the nation's surviving mutants starts here! Kitty Pryde tries to lead a nation of mutants. Meet Mach Two: former Morlock tunnel refugee turned mutant resistance fighter. Will she side with Kitty, or become a dangerous new enemy? Rogue gets an unexpected visitor as Storm helps Terra form the reservation. What is the Sentient Seed and why does everyone want it? And as the Iron patriot guest-stars, Mach Two's play for power takes a new turn - and leads to a fatal showdown. COLLECTING: Ultimate comics X-Men 18.1, 19-22.