Bloodmages (Combat Alchemists)

"It's like the Eideli have managed to concentrate all of the insubordination and inconsistency of their military into a single group- bloodmages. No matter how orderly the rest of the legions are, an average soldier remains similarly disobedient to one of most other nations, dragged down by the anchor that is the combat alchemist's lack of discipline. Even their gods seem in on the joke- almost every single one of their anointed saints to serve in the military have been bloodmages. The one who didn't was, of course, the Heretic Saint herself."

Commonly referred to as combat alchemists, despite the fact that they generally primarily rely on xiphaem as a means of attack. The "special ops" of Eideli forces which sports a disproportionately high number of loose cannons and straight up psycopaths, tolerated because the average member is capable of holding off an entire line of spindles.
Eideli xiphaem generally sees domestic usage more than anything. Xiphaem-based projectiles, on a strategic level (that is, barring exceptional individual casters), are less efficient than arrows logistically: weaker when made from dull blood, and far more expensive when made from sharp blood. Individual units may make use of the practice, but it's inefficient for the bulk of the military to do so when it relies on a streamlined supply train.
Often use orichalcum implements.
Bloodmages are seen as rather unhinged as a general group- it takes a special kind of person to deliberately choose direct combat as opposed to the safety of using automatons from a distance, after all. Additionally, the most effective ways of fighting with xiphaem are inherently quite brutal, since the entire magic is based in manipulation of blood. Eideli military doctrine acknowledges this to the point of teaching officers optimal strategies to avoid setting off their combat alchemists.
In general, Bloodmages are treated as completely separate from standard command structure other than their leader, ideally a figure who holds both their respect and themself has respect for the chain of command.
It's an old urban legend that combat alchemists wear masks because most of them are mass-murderers, kept on the military's leash due to their brutal effectiveness in combat. There is a grain of truth to this, though it's nowhere near as widespread as the rumors make it out to be.