JesiahTEG
Smash Master
#480 Uxie
Typing: Psychic
Ability: Levitate- Avoids all ground type moves including Spikes, and evades Arena Trap.
75/75/130/75/130/95
Full Support
Uxie @ Leftovers
Levitate/Bold
252 Hp/252 Def/4 Spd
Stealth Rock
Yawn
Knock Off/ U-Turn
Thunderbolt/ U-Turn
This is an excellent support set that is able to come into a hand-full of pokemon while setting up for his own teammates. Stealth Rock is as useful as ever, disabling focus sashes and making sweeps for pokemon such as Lucario and Scizor a lot easier. Yawn works perfectly with it, forcing your opponent to continuously switch and take SR damage or let something go to sleep. Knock Off can be used to remove Life Orb, Leftovers, or pretty much any item that may be annoying you. Thunderbolt rounds off the set so you can make a decent switch-in to Gyarados, while also meaning you aren't permanently crippled by Taunt. U-Turn can be used over either of the attacking moves to get a light hit in on switches, since Uxie tends to force some with Yawn.
Dual Screen
Uxie @ Light Clay
Levitate/Jolly
252 Hp/4 Def/252 Spe
Memento
Reflect
Light Screen
U-Turn/Stealth Rock
Uxie, despite being the most defensive of the three legendary pixies, was blessed with a wonderful 95 base speed stat to abuse. This can put the opponent in a lot of pain with Dual Screens and his 130 base defenses. Memento is the featured move on this set because it gives Uxie an edge over other Dual Screeners, meaning your opponent is even more crippled for your next pokemon to come in and easily set up. U-Turn is a great option on this set as it allows Uxie to live another day for those blasted screens. Stealth Rock is the superior choice if you want to use this as a pure "do or die" strategy, awfully useful early to mid game.
Trixie Pixie
Uxie @ Choice Scarf
Levitate/Impish
252 Hp/104 Def/152 Spe
Trick
Stealth Rock
U-Turn
Yawn/ Knock Off
This set makes an excellent starter for any team, as it gives the user both an offensive and defensive edge early game. With the current EV spread, you beat all the suicide starters out there, the fastest being Aerodactyl. This allows you to Trick the scarf onto them and take away their Sash, heavily crippling them. If they Taunted you trying to avoid the setup, they are now forced to switch out or be setup fodder to the rest of your team. This allows you to scout out the new switch-in with U-Turn, allowing you to get the appropriate match-up. Stealth Rock is useful on any team, and it is generally Uxie's job to set it up: especially during the early game. Yawn can force more switches to rack up Stealth Rock damage and allows you to further abuse U-Turn even further, or Knock Off can be used for when you're scared of something getting the scarf.... and liking it!
Extra Options
Rest and Sleep Talk can be put on almost any pokemon for durability, but Cresselia does it a whole lot better. Toxic and Thunder Wave are there in the form of delivering status, but again be sure not to make it an inferior Cresselia. Offensiely it can utilize Calm Mind and Water Pulse, though there's nothing really special at that. Ultimately, Uxie has a lot of similar options as Cresselia, so any set the spaceduck can pull off Uxie can usually try to mimmick.
EVs
Max HP over anything else: this helps to balance out her defenses and makes her take the most amount of hits needed. Otherwise, hit a magic speed number and pour the rest in defenses. The max you should go on the "Trixie Pixie" set is 417, which allows you to beat the fastest Taunter allowed in OU, Electrode, and Trick it before it can stop you.
Troublesome Pokemon
Uxie's biggest problem is finding out what to do after it has done its job: without being able to Yawn the opponent or set up Stealth Rock with an extra turn, late-game is just hell for the little pixie as she becomes less and less useful, usually having to rely on U-Turn or non-STABed Thunderbolts to do any damage. In the truest since of the word "counter", one does not exist since nothing likes losing their item, falling asleep, or being forced into an unfavorable match-up. However, once it loses the ability to do the first two options you should have little trouble in getting around it.
Written by Articanus.