http://www.smogon.com/bw/pokemon/umbreon
Why isn't this on site, it works just as well this gen. It royally screws mono-attacking Suicune if you Taunt it and switch to Storm Drain Cradily with Curse.
[SET]
name: Trap Pass
move 1: Mean Look
move 2: Baton Pass
move 3: Taunt
move 4: Yawn / Wish / Substitute
item: Leftovers
ability: Synchronize
nature: Careful
evs: 252 HP / 4 Def / 252 SpD
[SET COMMENTS]
-The main idea is to set up on bulky Water-types, such as Slowbro and Suicune, but it can take on most special attackers. Umbreon is designed to trap something and bring in a counter.
-Mean Look and Baton Pass are obvious for this set, so there's no reason to go into detail. Taunt blocks Roar and Whirlwind etc, and it goes first because of their negative priority. It also stops Pokemon that attempt to set up against Umbreon. Yawn is first in the last slot, just in case you predict a switch, or you're faced with an unfavourable matchup. It forces switches, but it can put a dangerous Pokemon to sleep. Wish can support teammates, and Umbreon's HP isn't too bad. Finally, Subsitute can be used on a switch, and it can give a teammate a safe switch in.
[ADDITIONAL COMMENTS]
-It's best to take advantage of Umbreon's defensive stats, but it can run 168 Speed EVs to outrun neutral 4 Speed Suicune, and 212 Speed EVs to outrun 44 Speed Suicune. Payback can be used if you're scared of Taunt, and it receives a boost from STAB. Moonlight is an alternative recovery move, but it only restore's Umbreon's health, and it relies on the weather being clear or sunny.
-Pokemon that can switch into Fighting- and Bug-types are good choices. Steel-types aren't a big issue as Umbreon can just Baton Pass against most of them, and it isn't going to do much anyway. Chandelure and Flygon can beat Steel-types. Chandelure can take on Fighting- and Bug-types as well. Nidoking can switch into Fighting- and Bug-types, as well as Rotom-H, Zapdos, and Crobat.
-Pokemon that can set up on the opponent or KO a specific threat. Pokemon with immunities can set up on Choiced attacks, or mono-attackers. For example, Storm Drain Cradily can beat mono-attacker Suicune that lack Roar, Azumarril can beat Grass-types and set up the risky Belly Drum, and Flygon can beat Electric-types. Mew is an interesting option as it can switch into Fighting-type attacks, and it has access to Taunt, Nasty Plot, and every stat boosting move in the game. It can prove devistating if it's faced with a weak Pokemon, such as Bronzong or Registeel. Mew is bulky, it can take some hits if EVd defensively. It doesn't even have to be that specific, you can simply use Umbreon to trap an opponent which another of your teammates counter, then bring them in.