Clefable @ Leftovers  
Ability: Unaware  
EVs: 252 HP / 252 Def / 4 Spe  
Bold Nature  
IVs: 0 Atk  
- Wish  
- Moonblast  
- Protect

Other viable options:
- Heal Bell
- Calm Mind
- Toxic
- Knock Off
- Encore
- Flamethrower / Ice Beam / Thunderbolt / all the random coverage you may need for a single specific threat if you have the luxury of having a "free" slot and feel the need to hit that specific Pokemon for whatever reason