House Terryn - Horus Heresy: The golden age of the Great Crusade was to be cut short by the supreme act of betrayal known as the Horus Heresy, during which the galaxy was gripped by the most bitter civil war Humanity had ever seen. The peace Voltoris offered, though well-suited to the prosperous centuries of the Great Crusade, left its people ill-prepared for the outbreak of this galaxy-wide conflict. Across the nascent Imperium, rebels clashed with Loyalists for the fate of Mankind. Space Marines fought Space Marines, Titans fought Titans and, alongside them, Imperial Knights fought Imperial Knights.Given the propensity of House Terryn to depart its home, Voltoris found itself lightly protected when the galaxy was split asunder, leaving its vast resources at the mercy of predatory forces loyal to either the Warmaster Horus or the Emperor. Only three dozen Knights stood in defence of Voltoris against all who sought to pillage the bounty of the world yet House Terryn stood amongst the greatest of Knight houses despite the peaceful reputation of its world.Indeed, the belief that Voltoris stood ripe for conquest lent arrogance to its invaders and few were the numbers committed to securing the world. Those that did descend upon the planet found themselves fiercely matched by the Scions of House Terryn, unable to claim victory in the face of merciless opposition.Under the watchful gaze of the Knight household, Voltoris was transformed from a peaceful world into one locked in an all-encompassing war, its people forced to raise arms against others for the first time in millennia. On both Voltoris and elsewhere, House Terryn stood firm against the forces of the Warmaster, refusing to surrender and awaiting the time that the Emperor's light would once more return to bring peace to its world.As Horus led his armies to Terra, he left a trail of destruction in his wake hundreds of light years wide. His forces seemed unstoppable as garrison after garrison fell before his might, or changed allegiance and sided with the traitorous commander.As the events of the Horus Heresy neared their tragic conclusion nine standard years after the fateful betrayal at Isstvan III, Horus was confronted and defeated by the Emperor aboard his flagship, the Vengeful Spirit, though the Master of Mankind was mortally wounded and had to be interred within the cybernetic life support mechanisms of the advanced psychic augmentation technology known as the Golden Throne.Though Horus lay dead at the hands of the Emperor, so high was the cost of victory that many sought solace in hounding the fleeing Traitors across the stars rather than face the task of rebuilding the shattered Imperium. This campaign of vengeance is known as the Great Scouring.The surviving knightly houses with the strength to fight unanimously joined in this crusade of retribution. Believing the honour of the many to be stained by the treachery of the few, the Imperial Knights hunted down the Renegade Knights that sided with Horus with extreme prejudice, seeking to redeem their tarnished reputation.Filled with righteous indignation, a combined strike force of Knights from Houses Terryn, Cadmus and Borgius annihilated the turncoats of House Devine as Imperial forces reclaimed the lost Knight World of Molech. But there were rumours that some of the traitorous Knights of House Devine went unaccounted for.Ten millennia after his house's founding, in 239.M35, Seuitonius Thucidides Terryn took the oath of allegiance to the Emperor of Mankind and his world became a formal part of the Imperium and a house of the Questor Imperialis. Under his auspices, Terryn Knights often fought alongside the Ultramarines Chapter of Space Marines.