This is actually my second UU team, but I'm still newbish at battling, and randomly threw some pokemon together in hopes of creating some synergy.. >_< UU is my favorite tier, and I want to be a good battler at it :P.
Venusaur @ Choice Specs
Modest - Overgrow
236 HP / 252 SpA / 20 Spe
~Leaf Storm
~Sludge Bomb
~HP Ice
~Sleep Talk
My special attacker, designed to hit as powerful as it can with Modest nature + Choice Specs. It can also function as my team's sleep absorber.
Steelix @ Leftovers
Impish - Rock Head
252 HP / 120 Atk / 136 SpD
~Stealth Rock
~Earthquake
~Stone Edge
~Roar
Physical wall of the team, and sets up SR and Roaring out to scout/phaze physical attackers setting up.
Altaria @ Leftovers
Mild - Natural Cure
112 Atk / 252 SpA / 144 Spe
~Draco Meteor
~Outrage
~Fire Blast
~Earthquake
Wallbreaker/mixed attaacker of the team. Needless to say, Draco Meteor will severely cripple any pokemon that doesn't resist it when combined with STAB + Life Orb boost. Fire Blast is there for Steel types that resist it.
Umbreon @ Leftovers
Careful - Synchronize
252 HP / 92 SpD / 164 Spe
~Wish
~Payback
~Yawn
~Protect
Team supporter. Can pass Wish to Altaria, who will be quickly worn down by SR/Life Orb recoil, and generally supports the team. Also can p-haze with Yawn, or cripple one of the opponent's team member. Umbreon can also bounce back any paralysis, burns, or sleeps.
Feraligatr @ Life Orb
Adamant - Torrent
28 HP / 252 Atk / 228 Spe
~Earthquake
~Ice Punch
~Waterfall
~Dragon Dance
Main physical sweeper for the team. Comes out at late game when most things are weakened by Altaria/Venusaur. Stat-ups, then proceed to sweep the opponent's team.
Lanturn @ Leftovers
Calm - Volt Absorb
40 HP / 136 SpA / 252 SpD / 80 Spe
~Surf
~Thunderbolt
~Ice Beam
~Thunder Wave
Special wall for my team. Lanturn can absorb special attacks quite well, and when Feraligatr is out and an electric attack is predicted, I can switch to Lanturn to absorb the hit, then T-wave the attacker/switch.
Any comment would be appreciated, please help me get better :)

Venusaur @ Choice Specs
Modest - Overgrow
236 HP / 252 SpA / 20 Spe
~Leaf Storm
~Sludge Bomb
~HP Ice
~Sleep Talk
My special attacker, designed to hit as powerful as it can with Modest nature + Choice Specs. It can also function as my team's sleep absorber.

Steelix @ Leftovers
Impish - Rock Head
252 HP / 120 Atk / 136 SpD
~Stealth Rock
~Earthquake
~Stone Edge
~Roar
Physical wall of the team, and sets up SR and Roaring out to scout/phaze physical attackers setting up.

Altaria @ Leftovers
Mild - Natural Cure
112 Atk / 252 SpA / 144 Spe
~Draco Meteor
~Outrage
~Fire Blast
~Earthquake
Wallbreaker/mixed attaacker of the team. Needless to say, Draco Meteor will severely cripple any pokemon that doesn't resist it when combined with STAB + Life Orb boost. Fire Blast is there for Steel types that resist it.

Umbreon @ Leftovers
Careful - Synchronize
252 HP / 92 SpD / 164 Spe
~Wish
~Payback
~Yawn
~Protect
Team supporter. Can pass Wish to Altaria, who will be quickly worn down by SR/Life Orb recoil, and generally supports the team. Also can p-haze with Yawn, or cripple one of the opponent's team member. Umbreon can also bounce back any paralysis, burns, or sleeps.

Feraligatr @ Life Orb
Adamant - Torrent
28 HP / 252 Atk / 228 Spe
~Earthquake
~Ice Punch
~Waterfall
~Dragon Dance
Main physical sweeper for the team. Comes out at late game when most things are weakened by Altaria/Venusaur. Stat-ups, then proceed to sweep the opponent's team.

Lanturn @ Leftovers
Calm - Volt Absorb
40 HP / 136 SpA / 252 SpD / 80 Spe
~Surf
~Thunderbolt
~Ice Beam
~Thunder Wave
Special wall for my team. Lanturn can absorb special attacks quite well, and when Feraligatr is out and an electric attack is predicted, I can switch to Lanturn to absorb the hit, then T-wave the attacker/switch.
Any comment would be appreciated, please help me get better :)