Fir build, how is it?

The Spd/Res A slot could be replaced with something better, at least in my opinion. Although I do understand that you're using it for the extra stats, there are A skills that can better benefit her.

Good luck dealing with units that have Guard.

First off always good to see some love put into Fir, she's my main merge project! Like others said the A-skill seems like the big thing to change. Other small might be the special, especially with wrath the extra cooldown from Iceberg could be good and Moonbow is another option I've been messing around with to see if I like it or Iceberg more (although my Fir is +atk/-res). My current Fir is below if you want to check it out. I'm really torn right now because I'd love to give my Fir Wrath or DC. But my only Nephenee is +atk/-res so I really don't want to give her up. And as far as DC goes I've never been able to summon a single Hector.

Edit: Forgot this picture had Threaten Def, as I also gave her Def Ploy and I've switched back to using that