I'd say 5th append is most helpful because she wants to use her skills as often as possible to raise the gauge. 2nd is next best since she can farm, but I don't know how good of a farmer she is yet because she's broken in the simulator. The looping doesn't look great based on the numbers. She's clearly designed for long fights.

Simply lovely👌

She's lvl.100, 10/10/5 with maxed 5th append and she can loop perfectly fine with Xu Fu + support Castoria + atlas uniform (I imagine she would do even better with double castoria). I don't have a leveled up black grail on my JP but I guess she can use it to 3T no plugsuit farm.

Her buddy system gives her NP +10% dmg per level which is absolutely cracked (you can get to +60/70% by turn 3 pretty easily) outside of the other buffs (instakill chance at lvl.4 and pierce invul + defense at lvl.7).

It all sounds pretty complicated but she seems quite good on both singlecore/multicore/CQ

She is quite good numbers wise, she gets to level 4 easily and once the bug is fixed where mystic code targeting makes her gain more points for levels she'll get to level 5 and 6 easily. At level 6 she is essentially doing zerk damage since her NP is being multiplied by 1.6x at that level if we account for zerks being 1.5x with the 1.1x hidden modifier they have.

Right, I hope they patch this soon!

The one piece swimsuit is real!

They fixed her in the simulator and I was wrong about the farming. A5 is definitely the way to go. Here's a worst case scenario for what she's capable of doing with plugless Black Grail, double Castoria. I went against Assassins instead of Berserkers because it makes no sense to use her against berserkers.