Tornadus is often overlooked in the Doubles metagame, even though it is one of the best physical attackers in the tier, courtesy of Defiant. Its other ability, Prankster, is also effective, allowing it to use support options such as Tailwind with priority. This is further backed by the fact it is one of only a few Flying-types with access to Flying-type STAB outside of Hidden Power in Acrobatics, which along with Defiant, allows it to rip through common Fighting-types such as Hitmontop. Additionally, Tornadus has good offensive stats, and its base 111 Speed allows it to outspeed and OHKO Latios, the fastest Dragon-type in the Doubles metagame.
While its strengths may make it seem like a true terror to face on the battlefield, it has weaknesses to three common attacking types, Electric, Ice, and Rock, and it is further crippled by mediocre 79/70/80 defenses. This leaves Tornadus completely open to common spread moves, such as Blizzard and Rock Slide, and common threats such as Thundurus. Fortunately, the raw power of Acrobatics and the pressure Defiant can apply to the opponent more than makes up for whatever flaws Tornadus may have.
This is Tornadus's defining set. Defiant allows it to laugh at Intimidate, which will only give its attacks more power. It can also gain power from Icy Wind, though the loss of Speed still hurts it. A Flying Gem-boosted Acrobatics is incredibly powerful; anything that doesn't resist it is going to take a lot of damage, and frail resists such as Thundurus will still take heavy damage as well. Superpower rounds out Tornadus's coverage, nailing Rock-types such as Tyranitar, who resist Acrobatics, very hard. The choice of moves in third slot is a difficult one. Taunt is generally the most common choice, stopping Trick Room, Tailwind, and more unfriendly status. Tailwind is also an option, allowing your team to move faster than the opposition, which can be very useful. U-turn stands out as an offensive option if your doesn't need any support, and also lets Tornadus switch out while doing some damage. Protect is in the fourth slot, as it allows Tornadus to guard itself against opposing attacks while its partner on the field handles things.Team Options & Additional Comments >>>
This set aims to make the most of Tornadus's other ability: Prankster. Thanks to Prankster, Tailwind goes up with priority, meaning Tornadus will almost always get Tailwind up. It also gives Tornadus access to priority Taunt, which helps shut down opposing Trick Room and Thunder Wave users, which a Tailwind team hates, making Tornadus a great team supporter. Acrobatics is the STAB attack of choice, dealing heavy damage to a variety of threats. Superpower can be used in slot 2, rounding out coverage, but Taunt is an option here as well. Substitute is useful on this set because it does not have Defiant, and most opponents would not dare to bring in their Intimidate-user on the turn Tornadus sets up a Substitute.Team Options & Additional Comments >>>
Tornadus has a variety of options. Icy Wind can be used to slow the opposition down. Unfortunately, Tailwind provides more Speed control, and there is little need for both in most cases. Air Slash, Heat Wave, and Grass Knot are all viable special attacking options, though in general, Tornadus's role is one of a physical attacker. Foul Play could see use on a bulkier set, dealing heavy damage to opposing attackers, but a bulky support set is outclassed by Thundurus in most cases. Role Play and Swagger are two great options for the Prankster set; Role Play can copy Drizzle, Sand Stream, or another ability off of a partner, resetting weather and helping your team in a weather war, but it can only be used once before Tornadus has to switch out. Swagger is a great move choice because it can give the opposition a lot of trouble from confusion, but it is basically a 50/50 coin flip, and is often as risky as it is rewarding. Still, it can be used on a partner with a Lum Berry or Persim Berry, essentially giving them a free +2 Attack boost before their assault. Yache Berry, Wacan Berry, and Charti Berry can be used to offset its weaknesses, but Tornadus prefers holding a Flying Gem for Acrobatics.
An entirely different set involving Prankster Rain Dance and Hurricane can be used. This is probably one of the best special sets Tornadus can run; utilizing a moveset of Hurricane / Focus Blast / Rain Dance / Tailwind, with an EV spread of 4 HP / 252 SpA / 252 Spe and a Timid Nature. Flying Gem and Damp Rock are both decent item choices for this set. Unfortunately, Thundurus outclasses this set too, and in general, Tornadus is best used as a physical attacker, since that is a role Thundurus, its life-long rival, cannot fill.
Checks and Counters
The easiest way to beat Tornadus is by using an Electric-type. Bulky Thundurus is probably the best, as it can nail Tornadus with a Prankster Thunder Wave (assuming Tornadus is running a Defiant set) and finish it off with a Thunderbolt. Rotom-W and Zapdos are also great choices to put a stop to Tornadus's shenanigans, as they can both OHKO it with a Thunderbolt. Ice-types such as Kyurem and Kyurem-Black are also great choices to put a stop to Tornadus. Faster Ice-types, such as Weavile, Choice Scarf Cloyster, and Choice Scarf Abomasnow, can take out Tornadus before it can hit back; Mamoswine and Abomasnow can also deal heavy damage through Ice Shard, though Abomasnow will need to watch out for Acrobatics. Cloyster and Mamoswine additionally get special mentions, as Icicle Spear will tear through a Prankster Tornadus's Substitute.
Rock-types that can tank a Superpower will also work out nicely if they get a safe switch in; Chople Tyranitar is an example of this. Like Ice-types, speedy Rock-types, such as Scarf Tyranitar and Aerodactyl, can take Tornadus down before it can attack. Terrakion can also be a large issue, especially if it is holding a Choice Scarf, though it will need some investment to tank a Flying Gem Acrobatics or Superpower. A less efficient way to beat Tornadus is Intimidate, which can weaken Prankster sets; however, you have to be sure that Tornadus is using Prankster, as Defiant sets will gain a boost from Intimidate and put you in a very bad situation. Additionally, Steel-types that can tank Superpower, such as Metagross and Jirachi, will also put a stop to Tornadus, as they can tank its attacks and hit hard in return.