I'm wondering what would be a good moveset for my zoroark. He's at level 41 and currently knows Low Sweep, Dig, Foul Play, and Night Slash.
Any suggestions?

Zoroark is mainly a Special attacker, so it's best to utilise Sp.Att rather than it's Att.

The Zoroark I'm running has the moveset

- Dark Pulse (Breeding, if you can't breed for it, Night Daze is a good replacement learned at lvl 64)
- Nasty Plot (Learns at lvl 54)
- Focus Blast (TM 52 - Located in Wellspring Cave)
- Flamethrower (TM 35 - Located in the Abundant Shrine)

Nasty Plot to Double your Sp.Att, Dark Pulse for STAB, Focus Blast for nice coverage and to hit other Darks, Flamethrower for Ferrothron basically.

If you want to go down the what I'm sure will be uncommon physical route Zoroark learns Swords Dance (TM 75 - Gift from one of the Seven Sages, Dream Yard), Keep Night Slash and Low Sweep, and then you can take the choice between U-Turn so you can Scout out your opponents counter for Zoroark (Remove Rememberer, Need a Heart Scale) or Flamethrower for Ferrothorn in the last moveslot. So...

- Swords Dance
- Night Slash
- Low Sweep
- U-Turn/Flamethrower