I've been playing with this team for a bit and it just sort of developed one guy at a time. It started with one guy and just moved from there. Here I go:
Anti-Lead Thundurus@Focus Sash
252 Speed, 180 SpA, 76 Attack
Thundurus' job here is to stop the lead of the opposing team from setting up stealth rocks, spikes, any stat boosting, baton passing etc with Taunt. Thunderwave is to ensure the rest of the team can just come in and sweep paralyzed guys after boosting. Wild Charge is for strong STAB and Grass Knot is for the Tyranitars and ground guys ie hippowdon, Swamperts, etc that resist wild charge and thunderwave. Oh, and the focus sash is to ensure that Thundurus can get at least one taunt/thunderwave combo out.
Boosted Durant@Rocky Helmet
252 Speed, 252 Attack, 4 SpD
Durant is fast, heavy hitter thats meant to boost attack and accuracy which was lowered due to Hustle against paralyzed foes. Rock Slide is for fire/flying/ice/bug types. Iron Head is for Rock/Ice flinching foes. X-Scissor is for dark/psyphics and massive STABS between the last two slots. Given with his stats, he's not a tank, but he can hold his own and could force changes with immunities.
Special Sweeper/Rain Dancer Galvantula@Shell Bell
252 Speed, 252 SpA, 4 SpD
Galvantula is weak to only 2 types, fire/rock which are covered by durant and others in my party. Assuming stealth rock wasn't put up due to Thundurus' prankster Taunt, Galvantula can enter this game at full health. With CompoundEyes, Thunder becomes a very reliable, powerful STAB move. Bug Buzz is very powerful and for the grass types that are resistant to Thunder. For those that are resistant to both of those, I have Energy Ball.
Wall Buster Terakion@Life Orb
252 Attack, 252 Speed, 4 SpD
Taunt is to stop Walls ie Blissey/Skarmory. Swords Dance to boost attack stat. Rock Slide for accurate STAB move and Sacred Sword is chosen over Close Combat because of the side effects of close combat. Terakion can always function as a Physical Sweeper also so thats why I chose that move.
Special Attacker Hydregion@Life Orb
Modest Nature (+SpA,-Attack)
252 SpA, 4 SpD, 252 Speed
Surf is for ground/fire/rock types that can hurt my team. Draco Meteor is for STAB. Flamethrower is for stubborn steel types ie Skarmory/metagross. U-Turn is if his SpA gets too low or encounters a problematic guy.
This last spot caused me the the most trouble. I thought about my weaknesses, fire, ice,fighting, dragon, water. And I determined that fire can be blocked in or stopped with terakion/durant/Hydregion. So I needed something that resisted ice,fighting and dragon and so came in a classic Metagross
Physical tank Metagross@Leftovers
252 Attack, 124 Def, 132 SpD
I used to have Explosion in that last spot, but given its downgrade in gen V, I switched it for thunderpunch. Bullet Punch for 1st priority STAB against troublesome ice/rock types. Zen headbutt for the fighting types that could cause problems for my terakion, hydregion. Earthquake for the fire/rock/steel types. and ThunderPunch for bulky waters that woudl try to KO with Ice Beam my thundurus, Hydregion, or water for Terakion.
The Overall strategy would be to force changes and screw up their strategies. It's a very diverse team, but a common thing is that all of them, but one benefit from the Rain Dance provided by Galvantula. Fire is weakened saving Durant, Galvantula and Metagross. Thunder gets 100%, not that it needed it. Hydregion doesn't care about the Rain boost to water since its resistant to water. But flamethrower may be hurt, but then again thats why it has Life Orb. Rain Dance woudl be used if needed ie Chandelure who can hurt my team with a will-o-wisp, overheat combo. So I know it needs help, but its a good first attempt. I"d appreciate feedback thanks :-)