Death Knights Of Crail

On the Daemon World of Dundee, in the rotting Fortress Monastery of Crail, the Death Knights Of Crail perform dark rituals in the name of their patron god Nurgle. And leading these rituals is the Grandmaster of Death and Decay, Chaos lord Proletius, a fallen hero of the Imperium of Man, now a ghost of his former self, he leads the Death Knights in battle, flying atop a rotten Heldrake, killing all who oppose his warband's advance.

Origins
Before their fall to the Ruinous Powers, the Death Knights Of Crail were honorable successors of the Imperial Fists. In battle they were fearless, sowing terror to the hearts of Xenos and heretics alike. At that time Proletius was still in his full strength, leading his Chapter to war.

Their fall came when they were fighting the traitors of the Death Guard on the planet of Dundee, during which Proletius was blown apart with his Honor Guard, when the Death Guard launched a volley of artillery that passed their defense line. The battle was won, but most of the Chapter was in ruins.

Proletius' soul, instead of going to the Emperor's Table like he believed, floated in the Immaterium, where the Chaos God Nurgle offered him a new chance, to fight for him, in a new, rotten, incorporeal form. Proletius, having lost his faith in the Emperor seeing the great churning inferno that was the Warp, and not the afterlife he was promised, accepted, and soon rose from the dead, letting out a chilling warcry.

His remaining brothers, upon seeing his resurrection, regrouped, and heard his speech of how Nurgle had granted him the power to come back to rise from the abyss of death. After he was done, the remaining Astartes tore off their purity seals, and marks of the Imperium, and proceeded to kill other beings on the planet, turning it into a plague infested hellscape. Their old Fortress Monastery of Crail, now in ruins, became their base of operations, from where they would sow terror to all other systems, and the Imperium of Man as a whole.

Appearance
The warband wears red armor with dark iron trims, adorned with symbols of Nurgle. The warband's armor has changed overtime, but Proletius' armor has remained the same since the day he died, given that he's a ghost. The warband tries to keep their diseased appearance concealed, and keep their armor clean and well maintained.

Tactics
The Death Knights of Crail are shock troops. They field large amounts of infantry, and light armored support. Proletius himself flies above his army atop a Heldrake, burning and blasting away all forms of resistance. The Death Knights will focus their efforts on one objective at a time, and once one objective is complete, they'll move to the next, then the next, and so on.

Siege Of Dundee, 032 M.42
The battle against the heretical Death Guard, which ended with the eradication of most of the Death Knights, and the death of Proletius. After this battle Proletius rose from the dead and the Chapter turned to Chaos worship.

Purging of the Fife System, 041 M.42
After their fall from grace, the newly formed Death Knights Of Crail destroyed most of the worlds of the Fife System, burning their cities to the ground, corrupting the soil, and raising the Imperial Guard defending the planets as zombies to devour the innocents. This set the warband on their new dark path in proper.