As Merlyn and King Arthur took dominion over Otherworld, Excalibur's former leader Captain Britain resisted their rule. Seeking asylum and enforcers with Lady Roma Regina in her Floating Kingdom, Captain Britain was gifted with a quest. To accomplish it, she would need to recruit ten knights, being able to travel to Krakoa through the Voltus Glade to form her team. Assembling Gambit, Rictor, Gloriana, Bei the Blood Moon, Rachel Summers, Shatterstar, and Shogo Lee, Captain Britain returned to Otherworld, where she then recruited Kylun and the recently resurrected Mordred. As the Knights of X, the ten champions learned that they should search for the Siege Perilous.^[1]