I haven't seen Stehnos overdrive since she's usually dead but you'll want to avoid Medusiana's as it's basically a party wide petrify. Euryale's just seems to be a weak single target hit.
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I'll grab it just for the sake of SSR but I'll probably end up priotizing the Eidolon and see what I'm left with after. Knowing how easy some stuff are to get from raids events now makes certain items not worth grabbing here.