If you want, you could switch the IV to +res -spd and have warding breath, she has crazy mixed bulk at +10, and if you dont have a res tank she soaks up red blue and colorless hits (Ninos and hector's come to mind)
I have a +10 Soren paired up with her. He even tanks some red mages barring W!Tharja (which Nowi can take care of), and even supports the team with chills and ploys.
Ah, i'm thinking a mixed core for me right now, Eirika/marth (he's high invested but 4*+10), Camilla and either Reinhardt or Nowi, depends on the bonus I have, both are +10, but tactics are toooooo stronk
I'm about to finish my Fae (have 160k feathers for her last merge and pulled the 11th copy). But she, like your Nowi, is just so standard that I don't feel like bragging here.
Guard is so good in Arena btw. I wouldn't change a thing about your Nowi.
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