I’m planning on +10 her (since I really like her both as a character and a unit), but I’m not really sure about what IVs should I use. The one I’m using right now is +Atk -Hp(She is already +2) but I just got a +Spd -Hp 4* version of her. Should I replace her?
(Current build:
—Lightning Breath+ (Def refine)
—Draw Back
—Aether
—Warding Breath
—QR3
—Threaten Atk 3
—Close Def 3 sacred seal)
Go +atk. A speed boon isn't very redeeming on Fae unless you dedicate yourself to it (which your build doesn't). She already has QR3 as an enemy phase unit, which should be enough. If you made her +spd without taking care to specialize her in it, it's not as though she could deny doubles anyway. Taking two hits will only charge her Aether faster, which is a good thing, and with the attention you're giving to her defense via close defense should be enough to sustain her.
I agree very much that Fae needs to go hard on spd if she's going to do it at all. It's very hard to invest both in her spd and def, so if she's going for spd she probably can't afford to get doubled and if she's going to get doubled then she needs to bunker down hard, which she can do.
If her team can buff her spd into the 40s (I really recommend no less than 40; 47 seems to be a good target to reach at +10 with buffs and ally support because 51 seems to be a number I see more than once but not 52) go +spd and change her weapon refine to get her on her way. Keep in mind that she'll need to attack into bold fighters because her speed isn't going to protect her from getting doubled and hit with an ignis/bonfire/etc. Otherwise I think +def is probably the best boon.
Fun fact: your current build might - just maybe - survive a hit from Y.Tiki Breath of Fog. That's a lot of res she has.
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