Balian's Rebellion

Balian's Rebellion was a lamentable event in Imperial history that occured in 674.M36, when a respected Astra Militarum General was secretly abducted and corrupted by the nefarious Chaos Warband known as the Forsworn. This inevitably led to the corruption of the world of Engrion, which was protected by the Rebutors Space Marine Chapter. With assistance from the Inquisition, the Imperial defenders were able to turn back an orchestrated assault by the Forsworn, but the planet was lost and had to be subjected to Exterminatus.

History
Valkar Balian was a respected General of the Imperium. He was in charge of overseeing worlds controlled by the Rebutors Space Marine in the Chiros Sector of the Segmentum Tempestus in the absence of a Coureon. Then, he was abducted by an agent of the Forsworn and corrupted thoroughly and entirely to the power of Slaanesh. Balian then returned to his stewardship of the Rebutors' worlds and instituted specific laws and punishments against political enemies until Rebutor Knights were dispatched to observe him. His treatment of certain citizens was almost fanatically kind, yet with others he was unspeakably brutal and cruel. For several months these circumstances remained, with the Rebutors growing ever more suspicious of the once revered General. Soon, screaming was heard in the night.

The Rebutor Knights bore witness to the start of an uprising; thousands upon thousands of residents upon the planet Engrion shouted heresies. The figurehead; Valkar Balian. The citizens had discovered the Ruinous Powers. Immediately, the Knights informed the rest of the Chapter of the heretical activity occurring upon Engrion. There was no other alternative than to initiate Exterminatus. The Inquisition was informed of the Chaos uprising of Engrion. Prior to their arrival, the Rebutors engaged cultists of Slaanesh in battle upon Engrion. Balian had been transformed into a heinous, corrupted beast. But he was only a pawn, one that served to sow rebellion in his worlds, to create a vanguard for the Forsworn's assault.

Once the Inquisition arrived in Sector, the Rebutors retreated from the planet in order to discuss matters of Exterminatus. However, before a decision could be made, a large fleet of Heretics emerged from the Warp, bearing the sigil of an eye. The Rebutor fleet engaged the forces of Chaos in battle, decorating the high orbit of Engrion with a barrage of bullets. Eventually, the Heretic Astartes were able to board the Rebutors' Battle Barge Redemption, immediately engaging the prepared Loyalists. The Forsworn had come, with revenge in their eyes.

The Rebutors fought valiantly against the Chaos Marines, losing few to the several waves of Forsworn. The close-combat preference of the Rebutors did not grant the Heretics the upper hand in battle. After a long battle, the Forsworn fleet began to retreat back into the warp. How they lost their advantage to the Rebutors, but the leader of the boarding force was mutilated by Arkann himself, so that the entire Warband felt and suffered from his failure.