Legion

Winter is coming. Such is the stern motto of House Stark, the northernmost of the fiefdoms that owe allegiance to King Robert Baratheon in far-off King's Landing. There Eddard Stark of Winterfell rules in Robert's name. Far to the north, behind the towering Wall, lie savage Wildings and worse - unnatural things relegated to myth during the centuries-long summer, but proving all too real and all too deadly in the turning of the season. Yet a more immediate threat lurks to the south, where Jon Arryn, the Hand of the King, has died under mysterious circumstances....

The Heresy came to Calth without warning. In just a few hours of betrayal and bloodshed, the proud warriors of the XIIIth Legion - Guilliman's own Ultramarines - were laid low by the treachery of their erstwhile brothers of the XVIIth. Now, as the planet is scoured by solar flares from the wounded Veridian star, the survivors must take the fight to the remaining Word Bearers and their foul allies, or face damnation in the gloomy arcology shelters beneath the planet's surface.