Salandit is a fast special sweeper. There's no question about that. So here's a moveset focused around that.
Salandit @ Focus Sash
Ability: Oblivious
Level: 5
EVs: 252 SpA / 252 Spe / 4 HP
Modest Nature / Timid Nature
- Sludge Bomb / Sludge Wave
- Flamethrower / Fire Blast
- Dragon Pulse
- Nasty Plot
Right off the bat, go for a Nasty Plot. You'll probably outspeed except for against faster mons, and you're guaranteed to survive to the next turn due to the Focus Sash. You'll want Sludge Bomb if you want a higher poison chance, and Sludge Wave if you want higher base power. Flamethrower offers higher accuracy than Fire Blast, but Fire Blast has higher base power. Dragon Pulse is a great move on Salandit because the only types that do well defensively against Dragon (Steel and Fairy) are weak to either Fire or Poison, your STAB moves. Modest and Timid natures both lower attack, and raise special attack and speed, respectively. The EVs are self-explanatory; special attack and speed are the two stats that Salandit focuses on, and the most useful for a fast special sweeper. HP is the default third EV sink, since it doesn't focus on only special or physical attacks like the defenses. Oblivious protects you from infatuation and Captivate, but more importantly also protects from Taunt (and Intimidate but we don't care about that).