[i]Knowledge is Power. Guard it well.[/i] -Imperial axiom.

Name: Rayvius 'Moyses' Skalterion

Chapter: Dark Angels

Equipment: 
Scout Carapace Armor/Mark VII Aquila Power Armor
Mk IIIa Godwyn Pattern Bolter
Guardian Bolt Pistol
Frag Grenade x4
Krak Grenade x4
Combat Knife/Chainsword

Biography: Rayvius was born on Aegyptus, a backwater planet that was abandoned by the Imperium during the Africanus Crusade for tactical reasons, primarily due to a warp storm due to hit and isolate the system. As soon as the Imperium abandoned the system, Dark Eldar appeared, enslaving the entire population. Rayvius escaped because a Dark Angels scout took him off the planet as a child, moved by his mother's plaintive pleas for deliverance. 
Rayvius was raised as a chapter serf by the Dark Angels and was a full marine by 16, where he promptly joined his battle-brothers in the Africanus Crusade. He never forgot his homeworld, and was haunted by his last moments with his mother. When he was 42, he requested to be sent to Aegyptus to help liberate the planet. The warp storm isolating the system had passed, but the Imperial forces deemed the planet not worth the expense of liberating it. He asked to join a unit of nine other Imperial specialists, agents and assassins. Rayvius' sergeant allowed his request, seeing how Ray's memories of his homeworld distracted him and hoping to excise him of the burden. Rayvius and his team became known on Aegyptus as the Plagues, and after a forty year campaign, managed to sow enough chaos among the Dark Eldar occupiers to allow a liberation force to be validated and force the Dark Eldar off the planet, culminating in a directed orbital bombardment and the assassination of the Archon of the Kabal. The people of Aegyptus immortalized him as the tenth Plague: the Angel of Death, and gave him the honorary name 'Moyses,' which he adopted without reservation. 
He went on to serve as a scout and a tactical marine during the remainder of the Africanus Crusade, though with no exceptionally notable heroics. At the close of the Africanus Crusade, he was offered a position in Deathwatch when he was 117, where he has spent the majority of his 90 years as a kill-marine. He was initially assigned to work with one Scout Sergeant Cyrus of the Blood Ravens Chapter, who instilled in him a thirst for knowledge about his enemies, and in his spare time is seen browsing forbidden archives on xenos, searching for new ways to exploit and kill xenos.

Notable Achievements: 
Was one of ten Imperial agents (known as the 'Plagues') sent to create a resistance operation on Aegyptus, and after a 40 year campaign of guerrilla warfare and insurrection, successfully assassinated the Archon.

Cleansed the Velcorn system's four inhabitable planets of a Genestealer infestation by himself within a week, accumulating a total kill count of 293 purestrain genestealers, 847 Hybrids of various generations, and two Broodlords.

Physical Description: Short black hair, has a burn scar on his left cheek. Otherwise, your standard Astartes.

Class: Scout/Tactical Marine

Personality: Rayvius is a loner, a trait cultivated during his time on Aegyptus and as a Kill-Marine of the Deathwatch. As he has spent half his life away from other Astartes, he is experienced in non-Astartes interaction, and is much more personable to non-Astartes than most Astartes are. He is quite knowledgeable on xenos, and can speak ork, eldar and tau, as well as High Gothic. He has a healthy thirst for knowledge. His century tenure to Deathwatch is coming to a close, but he has reservations returning to a chapter he has had little connection to. He has contemplated becoming a Blackshield, but feels that he should only take that option if he cannot connect to his old Chapter.

Rayvius can either be a tactical or a scout marine, so I included both options on his equipment and class. Please don't let my choices affect yours.