Wobbuffet, the Patient Pokemon
Weak to Dark, Ghost and Bug.
Resistant to Psychic and Fighting.
Base stats (HP / Atk / Def / Sp Atk / Sp Def / Spd)
190 / 33 / 58 / 33 / 58 / 33
Shadow Tag: As long as this Pokemon is in play, the opponent cannot switch out.
This Pokemon is classified as Uber.
Oh dear, Wobbuffet. If ever there were a candidate for the single most obnoxious Pokemon ever created, Wobbuffet is it. With an absurdly huge HP, both counter-style moves, and an ability that forces you to deal with the blob on his own terms, Wobbuffet can make life a living hell for anyone careless enough to switch in something that doesn't have a way to deal with it. Essentially, if you can't one-hit KO Wobbuffet, it'll come back and KO you in return.
Wobbuffet's most obvious asset is its obscene HP, but that pales when compared to the advantage Wobbuffet gets from its ability. Shadow Tag removes one of the biggest parts of battle - switching. As soon as the big blue punching bag comes in, you cannot switch out, giving Wobbuffet the ability to carefully select who it battles and when. Shadow Tag isn't quite as broken as it has been in previous generations, thanks to the introduction of U-Turn and the increased popularity of Baton Pass, both of which can get around Shadow Tag. Nintendo also modified the ability a little bit from R/S/E, allowing two Shadow Tags to cancel each other out so that two Wobbuffets don't get stuck in a snore-inducing 70+ turn Counterfest, which was the main reason Wobbuffet was banned to Ubers in the first place. But despite these changes, Shadow Tag is still an amazingly powerful ability simply because there's no real way to protect against it, short of putting U-Turn or Baton Pass on all of your Pokemon.
On the other hand, Wobbuffet shares a weakness of sorts with Blissey; Both Pokemon have amazing HP, but poor defenses. Wobbuffet has to pump EVs into Def and Sp Def in order to take boosted hits, especially in the higher-powered, more offensive arena that is Ubers play. His difficulty in taking hits from Pokemon like Swords Dance Arceus and Rayquaza is one of the main reasons Wobbuffet isn't often seen in Ubers play. The other reason is predictability. The blue blob learns a grand total of seven moves, eight if you consider the event-exclusive Tickle, meaning that once Wobbuffet comes into play, your opponent will know exactly what to expect.
Wobbuffet's predictability, however, doesn't have any real effect on the raw power it gets from Shadow Tag. Even if your foe knows what you're going to do, if they can't switch out, it's unlikely they'll be able to stop you before you Counter their face in.
That's the Way it is, Madam.
Wobbuffet @Leftovers / Focus Sash
Impish / Bold, Shadow Tag
252 Def, 252 Sp Def, 6 HP
-Safeguard / Tickle
This is it, the one and only moveset you're ever likely to see on a Wobbuffet - it simply doesn't learn enough moves to have any other worthwhile strategy. The strategy here is very simple; get Wobbuffet into play against something that won't instantaneously kill it, and use Encore. If Encore traps them into a physical attack, Counter back. If it gets a special attack, Mirror Coat. If they used a stat increasing move, either switch out to something that likes having a turn to set up, or use Safeguard and then switch out.
Weirdly enough, Wobbuffet learns Tickle through the NYC Pokemon Center. Tickle makes a great substitute for Safeguard - you'll be vulnerable to status effects, but you'll also be able to set an opponent up to let another Pokemon sweep. In the item slot, Focus Sash is a solid choice for play in Ubers, where it'll allow Wobbuffet to act as a revenge killer, taking one huge blast of damage and countering back for the kill. Lum Berry isn't a bad idea either, assuming you're using Safeguard, since it'll give you a chance to absorb a status effect and then set up Safeguard.
Wobbuffet's ability to pick and choose who it battles means you can afford to be careful, avoiding physical attacking Ghosts and special attacking Dark-type Pokemon, since there's little or nothing you can do to either of them. Two Pokemon you particularly want to avoid are Spiritomb and Dusknoir - Spiritomb doesn't really care what you do one way or another, since it is immune to both Counter and Mirror Coat, and can outspeed Wobbuffet and put him to sleep with Hypnosis. Dusknoir, on the other hand, can use Mean Look to trap you right back, and proceed to Shadow Punch Wobbuffet right in his creepy, creepy face. With a bit of caution, though, Wobbuffet can act a lot like Umbreon, trapping foes and setting them up for another Pokemon to take down.