Goodra @ Assault Vest(/ Wide Lens)
Ability: Sap Sipper
EVs: 252 HP, 252 Atk., 4 Sp. Def.
- Power Whip
- Iron Tail(/ Poison Tail?)
I'm surprised I didn't see a physical set. Well, not really. It's physical movepool is considerably worse than it's special counterpart; although it's Attack stat is quite usable. The idea is to switch into a Grass-type move and start tank-sweeping.
Outrage is its strong Dragon-type STAB, just... watch out for those pesky Steel- and Fairy-types. It unfortunately doesn't have the Dragon Claw option, although that makes sense (mushy Dragon Claw, kawaii! ^w^)
Earthquake is mandatory, being Goodra's most reliable powerful physical move, covering Steel-types if you're predicting that switchy.
Power Whip is there because... because it's strong? Ok, now we see the limits of Goodra's movepool on this side of the attacking spectrum... But still, Power Whip is a very nice option, covering Water- and Ground-types better than Earthquake.
The last move that I would recommend is Iron Tail. It covers your Fairy- and Ice-type weaknesses, but has shaky accuracy at best. Poison Tail is really only if you hate the low accuracy and want to be sadistic to the fairies with your critically poisonous tail, but it's not really a good idea because the power is severely lacking ._.
The Wide Lens is only mentioned here because you have two low accuracy moves with the Whip n' Tail, but if you want to tank those special hits, the Assault Vest is your new best friend.
The Nature and Evs are to help boost your slightly lesser Attack stat by any means possible, whilst the HP EVs help with your tanking.
Please keep in mind this is a surprise set designed to take care of what usually tanks Goodra's usual sets, i.e. Chansey/Blissey, other Goodras, Sylveon... and MegaGardevoir?
Oh, and, you're walled by Skarmory, Ferrothorn, Scizor, Forretress... but I'm assuming Goodra is going to be UU, so it should be fine, although if you really wanted, you could run Aqua Tail instead of Power Whip.