The latest Horus Heresy novel There is war on Signus Prime; Horus sends the Blood Angels to the Signus system, where an army of Khornate daemons waits for them. The Warmaster's plan is to use the flaw in the Blood Angels' gene-seed - which will later be known as the Red Thirst - to turn them to the worship of the Blood God. At the height of the battle, Sanguinius fights with the Bloodthirster Ka'Bandha. The Blood Angels fight for survival of thier minds and bodies