User blog comment:Koishi-Komeiji/Miyu Edelfelt/@comment-3393055-20180905081320/@comment-24965192-20180905133254

I tried an Arts Crit Lancer skill set. But since lorewise, her NP won't do damage, I opted to make her raw damage potential high, so there's that 2nd skill.

And yes, the Protection from Arrows skills come from Cu's install card. It's a rank lower than his due to being an imitated version. She is also not transforming into Cu (Card installing is disabled as a Servant), but rather she is already summoned as a Lancer.