I don't have any 5* exclusive at +10, either, and I've been playing since day 1. I think my highest is Ishtar at +5. I definitely get distracted by new stuff all the time, big part of that being new stuff at +0 is still miles better than old stuff at +10. Sentimentally, I'd like Elincia and Sigurd at +10, and wouldn't mind Ishtar or Ayra but there's no way I can justify spending orbs on that at this point. Summer Byleth is still really good so I might go for more copies of her, but I really doubt I'd be able to get +10.
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