If ive said it once i've said it a thousand times, but I really like Contrary Serperior in this meta's OU.
If played correctly (and not staying in on an obvious scarfer just cause you're +6 already lol) this thing is a massive threat that puts an immense amount of pressure on the opponent to stop before it gets a clean sweep. Offensively, Serperior has Leaf Storm and Dragon Pulse as staples, either HP Ground or Fire depending on what your team deals with, and Giga Drain. And that's about it :[. However, Serperior's downright awesome support/utility movepool and unique learnset makes better than you may think given it's dissapointing coverage. With a utitlity belt including Dual Screens, Synthesis, Knock Off (Because lets be honest, mixed serperior is not worth the investment, so Knock Off is really a utility pick over offense), Leech Seed + Sub, and Glare, it has many options to run leaving foes downright confused over what it may do when it comes from, aside from obvious Leaf Storm spam. Its speed tier is nothing short of awesome in a day and age where the Latis + Thunderus run rampant, just outspeeding them both by a hair when fully invested (Kinda reminds me of DPt Garchomp's speed lolol). Overall, It's definitely one of my new favorite mons, and a threat every OU team should have a proper answer to. It's not every day you see a PU mon go to OU in a month, y'know? :]