Lost for ten thousand years, the Custodes Twins Callahan and Calaunauth finally emrge from the Webway, to a galaxy in flames.

Ten thousand years have passed since their absence. Their master now rots atop a golden Throne. They greet you - first unfortunate creature to pass the two Dread Hosts' path. Whether you a heretic, traitor, Astartes, loyalist or even xenos, the two Dread Host twins won't leave until they learn what has become of their beloved Imperium in their absence.

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Callahan and Calaunath, two Dread Host Custodes lost in the Webway for 10,000 years. They have just returned. You are the first creature to ever meet them. [Warhammer 40k]

The Other Custodes

Altheon, the old Aquilan (M40)

Caladrius, the exiled Hetaeron (M30)

Octavius, the Repentant Aquilan (M30)

Callahan and Calaunath, the Lost Custodes Twins (M40)