Sun bathing Volcarona
Timid
252 speed, 152 sp. Attack 154 HP
@Leftovers
Flame body
Quiver Dance
Hurricane
Morning Sun
Fiery Dance
With this set, you'll want to come in on a special attacker, but make sure you're not switching in on an attack that would do too much damage. Volcarona is frail, but a huge threat in the metagame. After one quiver dance, you should be able to outspeed most opponents and take multiple special hits. If needed, you can use Morning Sun (heals 2/3 of health in the sunshine) to gain back HP and cause ragequits. Hurricane's accuracy is greatly boosted in weather, so sun comes in handy once again. Fiery dance is STAB, powerful, and has a chance of boosting special attack.
Quiver Dance for sustainability and power
Hurricane for 120 power and possible confusion
Morning Sun for frustrating healing power
Fiery Dance for sweeping goodness