Umbreon is a killer Special Wall, and Curse makes it a killer physical one too. After a Curse, it is not 2HKO'd by Moltres Fire Blast or Swellow's Facade, which makes it extremely impressive in my eyes.
How is Curse significant for taking Fire Blasts?
But I definitely agree that Umbreon is insanely good. I can certainly see Missy taking a hit in usage once more people realize how useful and hard to kill it can be.
With Shiftry, I don't think the problem is its offensive potential, it is the defenses and typing that makes it overall less useful than Venusaur. Grass / Poison has great defensive utility, Grass / Dark less so. You can check the odd Missy and Rotom, but only should they not be running HP Fighting or Will-o-wisp. I would definitely go with a set utilizing Explosion on Shiftry, to make it truly stand out amongst other Grass types. It is too slow to make good use of Nasty Plot without priority IMO.









