Uncanny X-Men
First Class: Knights Of Hykon

The world trembles as the sky begins to boil!

Professor X attempts a desperate rescue mission on the Starcore One satellite but a threat from galactic legend is waiting! Who are Burning Moon, Cloud Runner and Sky Song, and how are their fates tied to the X-Men? Earth faces destruction as the mutant heroes battle an unstoppable enemy The Knights of Hykon! (All this and Nick Fury too!)

Collecting Uncanny X-Men: First Class #5-8.