Thundurus

[SET]
name: Nasty Plot Sweeper
move 1: Nasty Plot
move 2: Thunderbolt
move 3: Hidden Power Ice
move 4: Focus Blast / Taunt
item: Life Orb / Leftovers
ability: Prankster
nature: Timid
evs: 4 Def / 252 SpA / 252 Spe


[SET]
name: Mixed
move 1: Thunderbolt
move 2: Hidden Power Ice
move 3: Hammer Arm
move 4: Taunt / U-turn / Thunder Wave
item: Life Orb / Expert Belt
ability: Prankster
nature: Naive / Hasty
evs: 32 Atk / 224 SpA / 252 Spe

[SET]
name: Prankster
move 1: Thunderbolt / Volt Switch
move 2: Thunder Wave
move 3: Taunt
move 4: Hidden Power Ice
item: Leftovers
ability: Prankster
nature: Timid
evs: 4 Def / 252 SpA / 252 Spe

[Other Options]
<p>On the Support set, dropping Thunder Wave and instead having both Volt Switch and Thunderbolt is an option, allowing Thundurus to retain the ability to 2HKO Drizzle Politoed and switch out of Pokemon that threaten it. However, it should be noted that Volt Switch will not work on Pokemon with an immunity to Electric-type attacks. To remedy this, U-turn may be used instead. Going with Life Orb and 3 attacks on this set is also viable; Hammer Arm can be used to good effect, as it always OHKOes lead Tyranitar. For this purpose, either Volt Switch or Thunder Wave can be dropped to make way for Hammer Arm.</p>

<p>Thunder is another STAB option which Thundurus can use, albeit only with rain support. Since it also has access to Rain Dance, Thundurus can set up rain itself, and put a 100% accurate Thunder to great use. Grass Knot can also be used to deal with bulky Water-types who are immune to Thunderbolt, such as Quagsire and Swampert, but is of little use otherwise. On the Nasty Plot set, if Focus Blast's poor accuracy is an issue, it can be replaced by Brick Break, which also removes the effects of Reflect and Light Screen. However, this is not advisable, since you lose a lot of power in return for reliability. Thundurus might seem like the ideal candidate to run a Choice Scarf set, but it is good only on paper. Thundurus is weak to Stealth Rock and thus cannot switch in and out frequently when it runs a Choice Scarf. Thundurus's other sets are also better suited to the metagame.</p>

<p>Toxic is another interesting option; even though Thundurus does not have the defenses to attempt Toxic stall, it can inflict status on walls and switch out with Volt Switch before taking too much damage, leaving the stage clear for a Pokemon adept at stalling to come in. This can be put to great use especially when finding a moveslot for Toxic on a staller is difficult. Wish Blissey benefits immensely, as it can run an extra recovery move instead of Toxic to stall out the poisoned foe. Thundurus can also set up Rain Dance reliably, since Prankster gives it priority. With the Drizzle+Swift Swim ban, Thundurus can fit in rain teams well, since it can support dangerous rain sweepers such as Kingdra and Kabutops. Rain Dance also allows Thundurus to shut down opposing weather teams with ease, and utilise a 100% accurate Thunder.</p>

<p>In terms of alternative boosting moves, Bulk Up is an option to help with physical sweeping, and can work in tandem with STAB Wild Bolt and other physical options such as Brick Break and Crunch. However, both Thundurus's physical movepool and defensive stats are rarely up to snuff for this sort of set. Lastly, Charge Beam is an option, but Thundurus needs to hit hard and switch, so it cannot afford to sit boosting its stats with weak attacks. Nasty Plot is generally the better choice for a boosting move.