You don't have to add it to the OP, I never said to add it to the OP, I'm just saying not to instantly disregard a set on the grounds that the pokemon in question doesn't do well in OU.  We can agree Ambipom isn't great in OU singles, but there are plenty of pokemon and sets that don't do well in singles, but shine in doubles and triples (Cressellia and Hitmontop spring to mind). That's where I would use that set. Anyways, let's move on:

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Sableye
Ability: Prankster
Item: Leftovers
Nature: Impish (+Def., -Sp. Att.)
EV's: 252 Hp, 130 Def., 128 Sp. Def.
Moves:
Swagger
Subtitute/ Mean Look/ Knock Off/ Psych Up
Recover
Foul Play/ Shadow Claw/ Payback/ Punishment

I've seen a few Murkrows pull off similiar sets, but I think Sableye could do it better with Leftovers and no weaknesses. Use Swagger to confuse the foe and raise their Attack. Then either Substitute to block any hits that make it through the confusion, Mean Look to keep them from running, or Knock Off to remove troubling items. After that spam Foul Play and use priority Recover as needed. Alternatively, you could try Psych Up to absorb the status change, then Shadow Claw/ Payback to take advantage of it or Punishment which does pretty good damage with the combined raised attack stat of you and your opponent (even more so if they have other stat boosts aswell).

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Sableye
Ability: Prankster
Item: Iron Ball
Nature: Careful (+ Sp. Def., -Sp. Att.)
EV's: 252 Hp, 6 Def., 252 Sp. Def.
Moves:
Will-o-Wisp
Trick
Recover
Night Shade/ Shadow Claw/ Payback/ Sucker Punch

Pretty simple. Will-o-Wisp to cripple physical attackers and for residual damage. Trick to take away the opponents item, ground Flying types/ Levitaters, and cripple speedy sweepers with a paralysis-esque speed drop (Aromatherapy that away Blissey!). Priority Recover for stalling burn damage, and the attack of your choice for speeding it along