Warhammer 40k - Horus Heresy Novella - Brotherhood of the Storm by Chris Wraight

As word of Horus's treachery spreads across the galaxy and with fully half of the Legiones Astartes turning their backs on the Emperor, Terra looks to the remaining loyalist Space Marines to defend the Imperium. One group, however, remain curiously silent in spite of efforts from both sides to contact them – the noble Vth Legion, Jaghatai Khan's fearsome White Scars. In the ork-held territory of Chondax, a bitter war has been raging since the Triumph at Ullanor, and only now do the sons of Chogoris return their gaze to the heavens...