This is the Bronzong set I've been using to fantastic success.
www.smogon.com/pokemon/dp/bronzong
[SET]
name: Screener
move 1: Light Screen
move 2: Reflect
move 3: Gyro Ball / Earthquake
move 4: Explosion
item: Light Clay
ability: Levitate
nature: Relaxed
IVs: 0 Spe
evs: 252 HP / 152 Atk / 8 Def / 96 SpD
<p> Bronzong is arguably one of the best transition pokemon in the game, able to come in on his multitude of resists and force many pokemon to switch out. This set is designed specifically to benefit the team by using every switch in to set up an 8 turn screen for the team. As far as attacks go, Gyro Ball will allow Bronzong to easily defeat fast opponents such as Gengar, Yanmega, and Deoxys... all of whom will struggle to do damage with the appropriate screen in place. Earthquake is always a favorable option on Bronzong for nailing Heatran, Infernape, and Magnezone switch-ins. Explosion rounds out the set by allowing a teammate a free switch in after a screen is in place. </p>
www.smogon.com/pokemon/dp/bronzong
[SET]
name: Screener
move 1: Light Screen
move 2: Reflect
move 3: Gyro Ball / Earthquake
move 4: Explosion
item: Light Clay
ability: Levitate
nature: Relaxed
IVs: 0 Spe
evs: 252 HP / 152 Atk / 8 Def / 96 SpD
<p> Bronzong is arguably one of the best transition pokemon in the game, able to come in on his multitude of resists and force many pokemon to switch out. This set is designed specifically to benefit the team by using every switch in to set up an 8 turn screen for the team. As far as attacks go, Gyro Ball will allow Bronzong to easily defeat fast opponents such as Gengar, Yanmega, and Deoxys... all of whom will struggle to do damage with the appropriate screen in place. Earthquake is always a favorable option on Bronzong for nailing Heatran, Infernape, and Magnezone switch-ins. Explosion rounds out the set by allowing a teammate a free switch in after a screen is in place. </p>