Emolga @ Leftovers/ Petaya Berry
Ability: Motor Drive
EVs: 252 Sp. Atk, 252 Speed
Nature: Timid
- Substitute
- Air Slash
- Charge Beam
- Roost
I saw someone using this set really well and ended up sweeping with just 2 moves, but that was over wifi. On Smogon, NU sees so much of Golem that you might want to go for HP Grass. You can also get lucky with flinch hax using Air Slash, so that's a bonus.
Ludicolo @ Life Orb/ Damp Rock
Ability: Swift Swim
EVs: 252 Sp. Atk, 252 Speed, 4 HP
Nature: Modest
- Rain Dance
- Surf/ Hydro Pump
- Ice Beam
- Giga Drain
Ludicolo is pretty popular in NU and for good reason. It's got a really good typing, fantastic ability that abuses Rain, and also powerful Water STABs that will further abuse Rain. Additionally it's got some good coverage in Giga Drain & Ice Beam.
Swanna @ Leftovers/ Damp Rock
Ability: Hydration
EVs: 252 Sp. Atk, 252 Speed, 4 HP
Nature: Timid
- Hurricane
- Surf
- Rest
- Rain Dance
This was a set I used a while ago. It's really good if you get Rain Dance up without getting hit, so maybe against Regirock when it's using Stealth Rock, but Swanna is so frail that it's harder to do that. I think if you could Baton Pass Substitute from something like Volbeat to Swanna, this set would do much better.
Butterfree @ Leftovers
Ability: Compound Eyes
EVs: 252 Sp. Atk, 252 Speed, 4 HP
Nature: Timid
- Quiver Dance
- Sleep Powder
- Bug Buzz
- Substitute
Smogon suggests Tinted Lens for this set, but imo Compound eyes is better just to get a 97.5% accurate Sleep Powder. Quiver Dance will make up for not super effective anyway. Watch out for Charizard and, indeed, Stealth Rock.