The Red Corsiars, oncce known as the Astral Claws, are a notoriously piratical group of Chaos Space marines with wildly different devotions to Chaos and others. Azazel was indeed once an Apothecary for the Astral Claws before their Heresy, which he wholeheartedly supported being one of the early adopters of destroying Imperial Iconography with red paint, the reason for the Corsairs name. Always an early adopter Azazel embraced the worship of all four gods wholeheartedly and with excitement, if not zeal. He was perhaps most loyal to the Prince of Pleasure and his rival, Khorne. His sadistic, specific way of experimentation and curiosity appealed to Slaanesh, whilst his thirst for blood and combat was paid to the Red God. He embraced his new freedom, offering any marine who sought it enhancement at the cost of free experimentation. Combining technology, anatomy, sorcerer and Daemonology truly horrific and deadly monstrosities came from his workshops. The Dark Apothecary even began to accrue a number of acolytes, pupils who wished to learn at his feet.
Throughout this time he had researched a particular surgery, one that he believed paramount to the Corsairs, the vaunted Berserker Surgery, one which turned marines into near mindless killing machines. For all his career, even before the heresy this operation had intrigued him, and now he could practice upon nigh endless subjects. Eventually he was able to capture a Khornate Berserker alive, using him to reverse engineer what had so thoroughly pledged his soul to Khorne. Thought it took many weeks, much screaming and many missteps Azazel was able to aapproach his Captain with wondrous news, he beleived he had perfected a bastardized version of the procedure and wished to grant his leader with Berserkers... for a certain price. This excitemnt led to his downfall, for he had shared his findings with his brightest pupil, who had already offered the captain the same deal, but for far less than his teacher asked for.
With thism the Captain had Azazel and his most Loyaly pupils detained, and declared to be the first test subjects of the Doctors new and miraculous 'breakthrough'. This would turn out to be a terrible mistake. Perhaps Azazel had overestimated his genius, or perhaps all his notes had not been found, or maybe his apprentice was simply less talented than he. For whatever reason, things went wrong quickly. Once the procedures were complete the subjects went wild with rage as expected, but it was not aimless or declared for the Blood God. Instead they were driven mad by visions of marines they did not know and battles they hadn't fought or held on to their spite. Azazel and his newly minted Berserker pupils cut a bloody swathe through his old Friends ship, murdering all that came near them, culminating in the death of his captain and the dissolution of his pirate fleet. However, his stat pupil had been mysteriously absent, and so lost in their maddening rage were the marines that they could not stop their warp jump into the void.
Noe, Azazel and his surviving pupils are adrift and aimless, their rage and petty lust for vengeance aimless and plagued by terrible madness. They seek salvation, and Azazel still cuts up foe after foe on and off the field, seeking a way to stop the maddening visions and voices in his head... if only he could see through all the blood... so much blood...