Here is my set. This is for my Pokémon story, but I still like the set. Not sure about Competitive Play but I think it has what it takes.
Luxray (M) @ Razor Fang
EVs: 252 HP / 252 Atk / 4 SpA
- Electric Terrain
- Wild Charge
- Giga Impact/Crunch
- Volt Switch/Ice Fang
Electric Terrain: If you have just a chance, just one little chance, you can set up and hit with a very deadly Wild Charge. And plus, no sleeping always helps. Sleep Powder Liligant got nothin' on Luxray.
Wild Charge: STAB, very powerful and deadly alongside Electric Terrain.
Giga Impact: Very powerful and is Normal, so it can hit almost every Pokémon, except for Ghosts. It also hits everything that Electric doesn't touch.
Crunch: Less powerful than Giga Impact, but its coverage is wider than it.
Volt Switch: STAB, also if you want to get out of bad scenarios.