Hi, do you maybe feel like sharing some headcanons for turcafinwë's favourite butcher?
His name is Foinelen Astalórë, in Aman he was one of the Wild Hunt oath-sworn to Oromë; he follows Celegorm to Beleriand, is knigthed by Fëanor, and quickly becomes the chief officer in charge of reconnaissance and intelligence among Celegorm's army. He remains loyal to him throughout ages until dying in the War of Wrath.
Foinelen is one of the oldest Huntsmen in Celegorm's immediate close circle, being closer in age to Maedhros than the younger cohort, and although technically nobility himself (his father traces his descent to Tata) he did not engage particularly gladly with political & high society life in Tirion. He's an individual with very little empathy for over-sensitivity and frivolity, and breaks his vow to Oromë because, like others, he thinks the Vala's refusal to pursue Morgoth and go to war with him is a betrayal of the core principle for which the Hunt as a whole exists; he leaves for Beleriand almost gladly. Henceforth he almost immediately establishes himself as a leading figure in the study of orcs and as such also valuable intelligence gathering -- he had studied biology and anatomy of both animals and elves prior to this, and is fascinated by the mystery of the origin of orcs and monsters (some say that some of the anatomical knowledge of elves made available to those in Aman came from Melkor; if this is so, Foinelen certainly doesn't speak of it).
He's one of the less outwardly raucous Huntsmen, but don't be misled by a stony and sarcastic exterior and definitely do not take any alcohol he will innocently offer to you, he's in charge of preparing his group's entheogens and it might be laced with datura.
Over the centuries, he amasses one of the largest if not the largest body of work on the bodies, lives and societies of orcs and other evil beasts, while simultaneously furthering knowledge of elven biology through autopsies of soldiers and thralls; not all of it is acquired through humane means by far (Celegorm's castle in Himlad has dungeons, though they are little spoken of by those that haven't become acquainted with them already), but being Celegorm's close confidante and in the upper echelons of the army, Foinelen has complete legal immunity to any accusations deeming the interrogation and torture of orcs impermissible. He's also the individual responsible for keeping tabs on their political concurrency, a job he is by no means poor at, so this is a liberty not awarded for nothing. The continuous effort, thousands of corpses and thousands of instances of interrogating orcs via ósanwë to get a complete, comprehensive idea of their lives and otherwise-inaccessible intelligence leaves a mark on him, but Foinelen has faith in its importance in the fight against Morgoth, so he's not going to stop regardless of how many nights he wakes up thinking about orcs cannibalising each other just to get out of the pits of Angband.
He loses his eye in the Dagor Aglareb, though he isn't particularly bothered by this and over time amasses a collection of glass eyes to wear during his formal appearances.
After the Dagor Bragollach and the death of Celegorm's previous lieutenant, he's promoted to lieutenant and made responsible for any military might under Celegorm's leadership save for his personal guard; he aids in integrating their forces into Nargothrondrim structures [read: subtly taking over Nargothrond's military] until Celegorm and Curufin are exiled, whence he, like other die-hard loyalists, follows without hesitation. Foinelen is not just in agreement with the sentiment pointed against Thingol, the line of Lúthien and Doriath as a whole that paints them as thieves and savages laying claims to superiority that only the Noldor have any right to, but among the foremost in spreading it; it's him that finds Dior's twins amidst the sack of Menegroth and hands them over to Celegorm's captain of guards to their death. He will go on to participate in the Third Kinslaying with what remains of the forces once loyal to Celegorm, which by then had become an insular group (they don't get along too well even with other, less extremist Fëanárian factions, as other elves are alarmed at their practice of tormenting captive orcs to kill time despite now very much knowing their elven origin and raiding non-Noldor settlements across eastern Beleriand for supplies), going as far as to slay one of his estranged siblings who had followed Finrod and arrived to Sirion with the refugees from Nargothrond, and remains loyal to his oaths until the end. Eventually, he dies to a poisoned arrow that wasn't extracted in time sometimes during the War of Wrath, not to be reembodied until millennia in the future.