I propose the below plot for this acquisition
Darius Quill
Details
Race: Strigoi
Age: 145
Lengtht: 100'
Weight: 2,200lbs
Occupation: None
Relation to PC: Opponent
NPC Type: Plot
Influence: 5
Description: Darius Quill was a powerful and revered Sil'Norai necromancer near the beginning of the age of Industry. He was known for his possession of an Essence Calcifier and experimented with the souls of animals with keen interest. It was known that he one day joined a Coven of World Mages in Daravin's imperial badlands with the intent to push his skill to the next level without the constraints of law or forced morality, and was never seen again.
In a last-ditch effort to protect the coven from a convergence of Badland Raiders, Darius performed what was meant to be a temporary Transference upon himself and placed his mind and soul in the body of a hulking creature he'd built from an expansive underground hive of chitinous insects. The shock and horror of realizing what he'd become broke his mind, and over a week-long fight, he lost the entirety of his sense of self and became the Strigoi he'd built.
Mindless, he culled the rest of the Coven and took up residence in the underground complex he'd sacrificed so much to protect. He has since sealed himself away, unbreathing and unfeeling in his endless undeath, and with him, lies his Essence Calcifier among the last of his surviving Necromancy Tools.
Skills
Darius is now tremendously massive, strong, quick, agile, and covered head to toe in thickly armored chitin. He is made entirely of Undead tissue and does not need mortal sustenance. The blades of his mouth, arms, head, and spine are nearly dull but rip through fabric and biology with incredible ease when struck with force. His armor can resist pistol fire, and his strength is enough to crush plate armor. Additionally, his body can be used as a long-ranged bludgeon which is very capable of killing instantly.
There are kinks to his armor as a result of rifle fire, but none so damaging that they impair movement or weaken him. These can be exploited to access his softer flesh.
Arkash has already been to the derelict remains that Darius has sequestered himself within, but hasn't ventured deep enough to encounter him yet. Arkash is aware of the presence of something in the chamber he is sealed within and will resolve to exterminate it when he moves into the Derelict as part of another plot. Without sufficient help, Arkash will need to repair himself via necromancy after the fight as his cardinal regeneration will be unable to repair his more serious injuries. After Darius is defeated, Arkash will obtain the essence calcifier.