Which One?

she needs +spd but -def bane will hurt so perhaps you can find +spd -res or +spd - hp? Or + atk -hp might be better than said options, i think.

+spd -def, but I suggest you find a better one, preferably +spd/+atk -res.

My Cousin Run On Her +Spd -Def. With Wo Dao+(Spd), +10,L&D And Speed + 3 As A Sacred Seal, She'll Reach 56 Speed.You Can Run On Her Flashing Blade+Moonbow, So She'll Have Moonbow Immediately.If You Can, Try To Get A +Spd - Res, So You Could Run On Her Fury.The Other It's Just Merge.

-spd is a very odd way to play Athena.