Item: Focus Sash
Evs: 252 Sp Atk, 252 Speed, 6 HP
I use this exact set on Showdown. The idea with this set is maximizing on predictions, and crippling those pesky steel or poison types. Encore is for locking a Pokemon into a move that you don't care about, like a Stat boost, a Substitute, etc, also allowing you to Toxic, when they switch out. Most players with make the switch then, to protect their sweeper. Allows you to fire out Stab, or Toxic, to cripple, when you predict well. Great for gaining momentum, and also allowing toxic to build up damage. The other two are just stab. I prefer power, over accuracy, and a reduced chance to poison, (30% Chance with Sludge Bomb, vs a 10% Chance with Sludge Wave) isn't an issue, because Toxic/Corrosion.
I chose Corrosion, over Oblivious, because, baring a Prankster with Taunt, almost no Taunt user outspeeds Salazzle, under normal circumstances (no Stat changes, no sticky web, no paralysis). Obviously Paralysis, Sticky Web, etc could pose a problem, but you never have a one Pokemon team, so you use your other team members to support.