[Archer tenses in the first moment, then gradually relaxes. He's not entirely fine with showing his face, but he trusts Caster enough to allow it. Even if he still has trouble with looking straight into his eyes.]

It's a bit more complicated. By now it's most likely muscle memory after who knows how many years of fighting, but in truth my skill lies mostly in analyzing the structure of any melee weapon I see. [he makes a face.] As long as the weapon is created from something that can be found in your world I can replicate it. Even if it's something as rare as bones of phantasmal beast. I can't create divine constructs, but most Noble Phantasms are possible to replicate.

[Looking away he makes a pause, his expression darkening. His skills are something he ironically can have some pride in, if used to craft training weapons as well as fix mundane appliances. What he's talking about now isn't what he's proud of. Ever. There's a possibility Caster will scoff and scorn his only ability.] When I project such copy I gain knowledge about the weapon itself, its creation and its history, as well as separate knowledge of how it was used.