The Adeptus Custodes are the guardians of the Emperor. They are a small, elite force that are similar in physical appearance to a Space Marine (Although their superior in physical combat). Unlike a Space Marine, Custodes are created by a unique, 'one off' process that is more time intensive than a traditional Space Marine. Due to this and their training, Custodes are more independent in their fighting style and martial prowess--whereas a traditional Space Marine fights better as part of a unit.

My Legio Custodes represent the Legion at the time of the Heresy and are led by the Emperor (Of course!).

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