The Angels of Retribution background

Screenshot from THQ's "Space Marine".

       The Angels of Retribution are my self made space marine chapter, who were betrayed by half of their chapter which turned to chaos, and were in turn excommunicated from the Imperium. The chapter was formed from two chapters, the Knights of Sanguinius, and the Lions of Caliban joining together to hunt down and destroy their fallen brothers. More details below...

The Knights of Sanguinius

• The Knights of Sanguinius were a Blood Angels successor chapter.
• Over half of their chapter was turned to Chaos during a battle against the Word Bearers.
• The Inquisition, not knowing that a large part of the chapter remained loyal, believed the entire chapter to be corrupted by Chaos and designated the chapter Excommunicate Traitoris.
• The loyal remnants attempted to prove their purity, but were attacked on site and all their communications dismissed as the lies of slaves to Chaos.
• Those still loyal vowed to hunt down their fallen brothers, and all of the forces of chaos to regain their lost honor.
• This new focus and discipline was used as a way to keep their minds pure and resist the temptation of Chaos that so easily took hold of their brothers. 

The Lions of Caliban

• The Lions of Caliban, were a successor chapter of the Dark Angels. 
•  The Lions of Caliban, often disobey imperial orders, and ignore requests for assistance to pursue their own objectives in the hunt for the fallen even more frequently than other unforgiven chapters.
• During a battle on an Imperial world that was being overrun by a Chaos cult and their summoned daemons, the Knights of Sanguinius joined the battle against the Chaos forces.
• The Lions of Caliban, seeing that the Knights were fighting against the Chaos forces as well, fought side by side with the alleged traitors.
• After the battle, the Lions allowed the Knights to depart without conflict in return for their assistance.
• Several Inquisitorial informants were stationed in the cities on which the two chapters fought together and reported that the Lions of Caliban were seen working with traitor marines.
• An Inquisitorial investigation was ordered and, upon confirmation that the Lions of Caliban were indeed working with the traitors, were themselves deemed Excommunicate Traitoris.
• The Grey Knights were dispatched to destroy the Lions, and during the following battle, a large portion of the chapter were destroyed, along with much of their fleet.
• The surviving marines were able to flee before they were completely destroyed.

The Angels of Retribution 

• The Lions of Caliban sent a transmission to the Knights of Sanguinius, and the two underpowered chapters joined forces in the fight against chaos, renaming themselves the Angels of Retribution.
•  Both chapters repainted their armour jet black with the right shoulder a dark crimson to indicate the union between the chapters.
• Unlike many of the renegade chapters, the Angels of Retribution did not seek refuge in the nearby Maelstrom, knowing the ruined fate of those who remained in it's warp infected space. Instead, they adopted a highly mobile strategy, and chose to constantly stay on the move, remaining in one place just long enough to complete their objectives.

The Enlightened:

• During a battle against the Word Bearers, six companies of the Knights of Sanguinius, were converted to chaos by the tempting words of the Word Bearer's Dark Apostle.
• The former Knights of Sanguinius renamed themselves "The Enlightened". 
• The 1st Captain of the Knights of Sanguinius renamed himself Kor'degrus, and became the leader of the Enlightened. He was elevated to a daemon prince after several centuries of slaughter in the name of Chaos. Kor'degrus wields an enormous black mace called Dâgalûr, which was gifted to him by the gods of Chaos. 
• Tharron is the Enlightened second in command after Kor'degrus. He is an equally brutal leader, and wields a power axe, and a demonically possessed lightning claw named Dagnrok. The daemon has been melding itself with it's wielder, eating away Tharron's flesh and armour, and replacing it with a portion of the daemon's own strength. 
• Harod who was originally a Chaplain of the Knights of Sanguinius, became the Grand Apostle of the enlightened. His corrupted words were what first set the Knights of Sanguinius down the path of heresy, and his abilities to sway the minds of others continue to turn worlds against the Imperium.
• Deep within the home world of the Enlightened, is a champion who's power, and skill in battle even surpasses the daemon prince Kor'degrus. Known as Apollyon, the champion remains in his chambers in communion with the dark gods until they personally call on him to fight in battles worthy of his skill. Apollyon never makes a sound. The warrior silently moves through the enemies of the dark gods like a shadow of death.

Main image is a screenshot from THQ's Space Marine customizer.
Other mages made with Bolter and Chainsword's Space Marine Painter.