Meaning of this 無手勝流の剣にしては！やる！line?

Question

So came across this line on this page (link, previous and following pages included also) and it has that very odd 無手勝流の剣にしては！やる！bubble on it that's left me stumped, (the context is a friendly sporting match with personal robots and the one who says the line then cuts off the other's robot's arms on the following page as shown, for what it's worth).

As far as I can tell from my dictionaries 無手勝流 just refers to a victory without fighting, or a personal/unique way of doing something, 剣 I assume is just referring to their opponent's sword though apparently can also refer to swordsmanship itself, にしては I assume is that Xにしては (for/considering X) meaning the construct has, and やる any of やる's many meanings. All together though I just can't come up with anything in my head that seems to make sense for that one bubble.

Also regarding the other circled KMFが剣術を使いやがった bubble (a KMF being the machines they pilot), I assume that'd be something like "Such swordsmanship with a KMF!" which they think as they get outplayed, but I'm not 100% certain. Would it be something like that?

Thanks for any help.

Answer 1

やる by itself can mean "do things well", and やる! in such a context means "(You're) doing well", "Well done" or such. Its variations include やるな, やるね, やりますね, and so on. Have you seen やった! (= "I did it!"), which I think is in the same vein?

I think you understand the 無手勝流の剣にしては part correctly. So the sentence roughly means "For/despite his own way of swordsmanship, he's doing well".

KMFが剣術を使いやがった simply means "(The opponent's) KMF used 剣術!", where this 剣術 refers to a specific "(special) move/attack" using a sword. Or it may mean "KMF used a sword for fighting!" if he was not expecting the opponent would use his sword. やがる is discussed in another question: How to use the inflection "やがる"?

Answer 2

・In this context 無手勝流 conveys the idea of not belonging to any established school of kenjutsu, or of being a school of its own, that is, being a self-taught swordsman.

・剣 here refers not to the weapon itself but to the swordsmanship, or by further extension the swordsman himself.

・The やる means (be) good (at something), skilled, competent, etc. And you are right about the にしては.

Putting it all together we get something like:

For a self-taught swordsman, he's/you're good!

About he's/you're, I couldn't well decide whether the speaker is thinking to himself out loud (in which case he's would be appropriate) or directly speaking to the opponent (in which case you're would be the right choice).

The curious use of ! in mid-sentence in the original is unusual (it's like "For a self-taught swordsman! he's/you're good!") but understandable.

Also, I'm ignoring the fact that it's not a person but a mecha. Well, a person in a mecha.

"KMFが剣術を使いやがった" appears to suggest that the fact that the KMF is using kenjutsu at all is the cause for the speaker's surprise ("A KMF wielding a sword?! What the heck?!"), rather than how good it was at it (of course that was probably part of the surprise, but still).