User blog comment:DirgeOfCerberus111/Adeptus Custodes Vs. Grey Knights/@comment-2253300-20110819114042

Grey Knights. The Custodes are a defensive army that has not had much real fighting since the Horus Heresy. Furthermore Grey Knights are all Psyker, and powerful ones too. Besides all this the only fight that the Custodes had since the Heresy was on Pluto, and they had their asses handed to them by the Death Guard, more specifically the Lords of Decay.