Alright. I don't have too much experience with Drought teams, but I hope you'll find this helpful.
So we'll start with Ninetales, obviously. You need this Poke for a team, blah blah blah you know this already. To start you off, I'll suggest that you run a simple offensive set, featuring Fire Blast / Solarbeam / Sunny Day / Hidden Power Ice. This set is mostly designed to lure in and eliminate Politoed and Tyranitar, which wins you the weather war. Predict a switch in, use Sunny Day, and you've just put a lot of pressure on your opponent while halting any momentum your opponent hoped to gain. Solarbeam is a 2HKO on any Tyranitar at best, while possibly OHKOing Choice Band Tyranitar after Stealth Rock damage. This set also beats the defensive Tyranitar set, as it cannot KO you before you KO it, due to a lack of Stone Edge / Rock Slide on that standard set. The only Politoed set that scares this Ninetales is the Choice Specs set, as Hydro Pump always OHKOs after Stealth Rock damage. With these two big threats eliminated, Ninetales has pulled its weight and has opened up a sweeping chance for the team's Chlorophyll sweeper(s). This is a very aggressive set, making it very reliant on good prediction skills.
With any sun team, you need to make sure you can abuse the weather. Fortunately, Venusaur is a great abuser of Drought due to Chlorophyll. A specially offensive set featuring Growth / Giga Drain / Hidden Power Fire / Sleep Powder. This set works very simple in practice. Bring in Venusaur, incapacitate a Pokemon with Sleep Powder, set up a Growth and sweep them. Obviously Pokemon with resistances to Grass and Fire are huge problems (being any Dragon-type, as well as Heatran), so let's beat them next.
I consider Choice Scarf Terrakion to be an almost universal check to any of OU's Dragon-type Pokemon, with the only real exceptions being Latios and Garchomp. Dragonite, Salamence, Kyurem-B and Hydreigon are all scared out by this magnificent beast, while it also beats Heatran in the process. This further helps set up for a Venusaur sweep.
You'll need some more support now, because of Ninetales' mediocrity. Rapid Spinners naturally fit well in this slot, such as Forretress or Donphan. However, I'm going to suggest a rather different approach: Xatu. With Magic Bounce, you can set up your own hazards using your opponent's turns. This really annoys teams that rely on Deoxys-D for their hazards. Not to mention that Xatu got Heat Wave in BW2, which lets it beat Forretress and Ferrothorn, two Pokemon that Xatu usually has to switch into to get hazards up. Like the Ninetales set I suggested, this is a very aggressive set, which relies heavily on prediction to get anywhere. You'll get better at prediction as you play, so perhaps start with a rapid spinner like Forretress or Donphan and work your way towards Xatu as you play more. For Xatu's set, I would use U-Turn / Heat Wave / Toxic / Roost.
Right now, this opens you up a lot to Terrakion, who only really fears Venusaur when the sun is up. Landorus-T is a great fit at this point for a few reasons. The first being that it beats Terrakion, which is good. The second point is that it provides Stealth Rock support, which is, again, good. The third and final point is that it has U-Turn, giving it great offensive momentum with Xatu. You can U-Turn around to get around threats like Tyranitar who really still annoys you, but hates seeing Terrakion come in. U-Turn is a difficult move to punish, because of the switch initiative.
For the last spot, we really need some sort of defensive Pokemon. Right now, Ninetales, Terrakion and Landorus-T makes a total of three water resistances, while your only option against them is Venusaur. For your last option, I'm suggesting a Calm Mind Latias set, who acts as an excellent way to beat several threatening Pokemon, such as Rotom-W, Breloom and Keldeo. Two water resistances are generally a staple on every team now due to how common rain is, and Latias generally loves beating things in the rain.
So in summary, here's the team I suggest you use.
[animate]ninetales[/animate][animate]venusaur[/animate][animate]terrakion[/animate][animate]xatu[/animate][animate]landorus-t[/animate][animate]latias[/animate]
This team may look very weak to Mamoswine. However, you can check it with both Venusaur and Terrakion. Venusaur can survive an Ice Shard after Stealth Rock, and OHKO with a Giga Drain that doesn't even need to be boosted in power. Terrakion scares it out due to Close Combat OHKOing. With smart play, it shouldn't be a problem. Cloyster make also look like another insta-loss for your team, but Venusaur outspeeds Cloyster in the sun, while OHKOing with Giga Drain.
