Cincinno
HP: 75 Atk 95
Def: 60
SpA: 65
SpD: 60
Spe: 115
I think Cinccino is easily one of the biggest threats in the entire tier, and that's why I believe it should be S Rank. Skill Link is what makes Cinccino such a force in the metagame, allowing it to break through Substitutes and proceed to sweep an entire team if it isn't prepared. Pair it with a Life Orb or Choice it and it suddenly becomes the most potent late game cleaner in the whole tier. With a base speed of 115 Cinccino is able to out-speed many of its victims provided they aren't carrying priority, and also makes it a viable scarfer. Once Cinccino's main threats are eliminated it can effortlessly be the end of the game.
Of course this doesn't go without saying Cinccino isn't the perfect Pokémon, and that's why it's been able to hold its place in NU. Nontheless I believe it can still easily be classed with the most prodigious mons in the metagame. Cinccino even becomes a viable wallbreaker when it's wielding a Choice Band, as Tail-slap 2HKOs everything that doesn't resist. Access to U-turn is great for getting itself out of some sticky situations, and Bullet Seed can hit Rock types and other Pokémon that resist Tail Slap. Cinccino also has viability running surprise sets with moves like Captivate and Charm that allow it to lower the opponents stats a couple stages and catch them off-guard, as well as Thief stripping the opponent of their item and taking it for your own benefit. Overall, I believe Cinccino is able to prove its status worthy of the highest ranked foes in the metagame.