I am really new and I decided to try UU. The team I made have done pretty good compared to my other teams. I laddered to around 1500 before I decided to post my team here.
There is not much in Team Building. I decided to go with my favourite Pokemon (Flygon if it wasn't obvious) but there is no need to keep it if there is another Pokemon that does the job better. Kingdra was then added. The other Pokemon where just added because they are good.
Flygon @Choice Scarf
Trait: Levitate
EV's 252 Att 252 Speed 4 SpD Jolly
Earthquake
U-Turn
Outrage
Superpower
ScarfGon is my revenge killer. Superpower helps me against some Pokemon which Fire Punch or Stone Edge can't. I might Change to Stone Edge if it is really a better option. I don't feel like running Fire Punch as the it would still take me a lot to take down Bronzong. The rest is a typical ScarfGon set. ScarfShao might be better and I might try it out in the future.
Kingdra @Leftovers
Trait: Sniper
EV's 252 Att 252 Speed 4 SpD Adamant
Outrage
Dragon Dance
Waterfall
Substitute
SubDD Kingdra. Set up your DD's while hiding behind a substitute. Sniper to get some hard critical hits. Leftovers to heal while Kingdra is behind a sub. Adamant over Jolly to hit harder (I don't know if I miss to outspeed any important Pokemon and if then, I'll change it to Jolly). There is no Rain Dance in my team so Swift Swim won't be helping a lot. I could use it to counter Rain Dance teams (I haven't meet many and I don't have a problem against them so I don't think I would have to change it).
Heracross @Flame Orb
Trait: Guts
EV's 252 HP 252 Att 4 SpD Adamant
Close Combat
Megahorn
Stone Edge
Swords Dance
I had IntimidateTop here. It was my Spinner and could use Stealth Rock. Heracross has good offensive power thanks to Guts/Flame Orb + Sword Dance. Maybe change it back to get some Hazards/Spin or change it to MoxieScarf Heracross. It would be kind of redundant because of ScarfGon but I might change it.
Crobat @Black Sludge
Trait: Inner Focus
EV's 176 HP 192 Att 4 SpD 136 Speed Jolly
Brave Bird
Taunt
Toxic
Roost
Brave Bird is the STAB move. Roost and Black Sludge help if switching into Stealth Rock or getting heavily hit. Taunt stops Pokemon from setting up spikes, SR, Burning, etc. Super Fang halves the HP to Pokemon and/or to help against Pokemon which resist your attacks. EV's to outspeed most of the format, having a fair HP, hit hard and stopping Porygon 2/Z from getting + SpA.
Empoleon@Leftovers
Trait: Torrent
EV's 252 HP 252 SpA 4 SpD Calm
Stealth Rock
Roar
Scald
Ice Beam
Thanks Teapot for recommending me Empoelon! It has done pretty well. It has done much better than Cofagrigus. It is my only Hazard setter and can counter Kingdra (even if I haven't find much). Roar has helped to weaken lots of Pokemon (and getting rid of Swampert).
Chandelure@Leftovers
Trait: Flash Fire
EV's 68 HP 252 SpA 4 SpD 184 Speed
Shadow Ball
Fire Blast
Substitute
Pain Split
It has done pretty good too. It outspeeds most Ghosts thanks to the EV's. I haven't used Flame Body much. Sometimes it would help having Flash Fire. Substitute + Pain Split have kept me alive lots of times and I am glad with the set. Leftovers will help with Chandelure lasting even more.
There is not much in Team Building. I decided to go with my favourite Pokemon (Flygon if it wasn't obvious) but there is no need to keep it if there is another Pokemon that does the job better. Kingdra was then added. The other Pokemon where just added because they are good.

Trait: Levitate
EV's 252 Att 252 Speed 4 SpD Jolly
Earthquake
U-Turn
Outrage
Superpower
ScarfGon is my revenge killer. Superpower helps me against some Pokemon which Fire Punch or Stone Edge can't. I might Change to Stone Edge if it is really a better option. I don't feel like running Fire Punch as the it would still take me a lot to take down Bronzong. The rest is a typical ScarfGon set. ScarfShao might be better and I might try it out in the future.
Kingdra @Leftovers
Trait: Sniper
EV's 252 Att 252 Speed 4 SpD Adamant
Outrage
Dragon Dance
Waterfall
Substitute
SubDD Kingdra. Set up your DD's while hiding behind a substitute. Sniper to get some hard critical hits. Leftovers to heal while Kingdra is behind a sub. Adamant over Jolly to hit harder (I don't know if I miss to outspeed any important Pokemon and if then, I'll change it to Jolly). There is no Rain Dance in my team so Swift Swim won't be helping a lot. I could use it to counter Rain Dance teams (I haven't meet many and I don't have a problem against them so I don't think I would have to change it).

Heracross @Flame Orb
Trait: Guts
EV's 252 HP 252 Att 4 SpD Adamant
Close Combat
Megahorn
Stone Edge
Swords Dance
I had IntimidateTop here. It was my Spinner and could use Stealth Rock. Heracross has good offensive power thanks to Guts/Flame Orb + Sword Dance. Maybe change it back to get some Hazards/Spin or change it to MoxieScarf Heracross. It would be kind of redundant because of ScarfGon but I might change it.

Crobat @Black Sludge
Trait: Inner Focus
EV's 176 HP 192 Att 4 SpD 136 Speed Jolly
Brave Bird
Taunt
Toxic
Roost
Brave Bird is the STAB move. Roost and Black Sludge help if switching into Stealth Rock or getting heavily hit. Taunt stops Pokemon from setting up spikes, SR, Burning, etc. Super Fang halves the HP to Pokemon and/or to help against Pokemon which resist your attacks. EV's to outspeed most of the format, having a fair HP, hit hard and stopping Porygon 2/Z from getting + SpA.
Empoleon@Leftovers
Trait: Torrent
EV's 252 HP 252 SpA 4 SpD Calm
Stealth Rock
Roar
Scald
Ice Beam
Thanks Teapot for recommending me Empoelon! It has done pretty well. It has done much better than Cofagrigus. It is my only Hazard setter and can counter Kingdra (even if I haven't find much). Roar has helped to weaken lots of Pokemon (and getting rid of Swampert).

Chandelure@Leftovers
Trait: Flash Fire
EV's 68 HP 252 SpA 4 SpD 184 Speed
Shadow Ball
Fire Blast
Substitute
Pain Split
It has done pretty good too. It outspeeds most Ghosts thanks to the EV's. I haven't used Flame Body much. Sometimes it would help having Flash Fire. Substitute + Pain Split have kept me alive lots of times and I am glad with the set. Leftovers will help with Chandelure lasting even more.
Cofagrigus@Life Orb
Trait: Mummy
EV's 252 HP 4 SpA 252 SpD Calm
Nasty Plot
Shadow Ball
Pain Split
Will-O-Wisp
Hitmintop@Life Orb
Trait: Intimidate
EV's 252 Att 252 Speed 4 HP Adamant
Sucker Punch
Mach Punch
Rapid Spin
Stone Edge
Trait: Mummy
EV's 252 HP 4 SpA 252 SpD Calm
Nasty Plot
Shadow Ball
Pain Split
Will-O-Wisp
Hitmintop@Life Orb
Trait: Intimidate
EV's 252 Att 252 Speed 4 HP Adamant
Sucker Punch
Mach Punch
Rapid Spin
Stone Edge