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I'm paranoid the hidden power needs might change if she goes to Ubers. Also, Is ground still worth using with Aegislash banned from OU?
I'm inclined to get one Naive (hidden power doesn't matter, but electric or ground works), two Rash with Electric and Ground, and one Naughty (hidden power doesn't matter either).
If she were to go to ubers, would her hidden power needs drastically change or would she be rendered unviable in that tier? I think between her speed tier, typing, and beast boost, she would have a lot going for her still.
ground hits toxapex and alola marowak, two otherwise sound switch-ins. if she hits uber, i hold doubts about her viability, but we'll see. i personally hope she stays in ou, but i wouldn't be too mad if she gets banned.
pheromosa may have a niche as a rapid spin user in uber, but lunala and giratina-o makes that niche pretty tough. other than that, it's kinda hard to justify using it over something like deo-a, which hits much, much harder and has better coverage. it's not like the 1 extra base speed stat is going to do much to carve itself a niche over deo-a, which outruns pretty much every notable unboosted uber.
One Quad Flawless Naive
One Hidden Power Ground Naughty
One Hidden Power Electric Rash
One Hidden Power Ground Rash
I'm not sure which one to bottle cap up first, but I seem to recall you mentioning that the Naive Mixed Attacker Pheromosa will probably be the most viable (U-Turn/High Jump Kick/Poison Jab/Ice Beam) @Life Orb or Expert Belt.