There was a post in the fave Pokemon thread about making Sandslash viable. Here's my Stab at it.
Right now its Theorymon but here's what I think.
I think you have to first maximize his respectable Attack and Defenses and make over use of his ability Sand veil. It would seem that Sandslash would work great in a battle where you could make use of both Trick Room and Sandstorm. This way you wouldn't have to worry about its abysmal base speed of 65. I think this set with a little support from its teammates could work well. First the Moveset:
Sandslash
- Earthquake
- Shadow Claw/Night Slash
- X-Scizor
- Swords Dance
Item Attached: Bright Powder
Ability: Sand Veil
EVs and Nature:
EVs: 4 HP / 252 Atk / 252 Def
Adamant Nature (+Atk, -SAtk)
The idea behind this set isn't just the set itself but who I think would pair nicely with the Pokemon those being: Tyranitar, Jellicent and Salamence. The idea is simple (I'm sure you're seeing it already). Tyranitar is giving you two things you're going to need to give you that little extra hit when Sandslash comes in: Sandstream and Stealth Rock. Given Sandlash's acceptable but not great base attack of 100 you're going to need that little bit to come in unless you were using Life Orb.
You're Second Teammate is Jellicent. Giving its great Bulk, access to Trick Room and able to Absorb one of Sandslash's threat (i.e Water). IMO its a great choice to making Sandslash work cause it makes it go first, covers not only one of its weaknesses to water, but can also cover Tyranitar's super huge weakness to fighting.
Now Salamence. Why cause of the glaring weakness to Grass (and covering Water as well) that has been created for the team. Given Salamence's typing and coverage options it can help to deal with Sandslash's (and the others) weakness to Grass.
Also thinking that Breloom could also be good for more defensive grass blocking and its access to Spore.
Lemme know what you think. I'm also going to test this theory out on PO sometime this week and let you know how it does.