I had recently summoned a +Spd -Hp Nino.The other Nino I had for much longer and invested into.I got 20K feathers right now, but am planning to promote a -Hp +Spd (Coincidentally) Pricilla to 5*.Should I bother investing into Nino, or do something else with her?
Speed is the most important stat of a Bladetome mage, unless they're a slow mage like Lilina.
If you already had plans to 5* Priscilla, then I say to for for her first, then do Nino another time. If you've already invested in a Nino, and she works fine, then it sounds like she really isn't that much of a priority.
I would say go for Priscilla first since a +Atk -Def Nino isn't bad at all. But for the long run, I would switch her IVs by promoting a +Spd one and merging your old one into her (this way you will keep all skills your old one had). +Spd is just incredibly good on Nino
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