Originally Posted by Fat Rajaion Tagami
Zorua: - High/Top Tier (the odd playstyle to use it probably means high)
Availability: You get one for free in Driftviel (Midgame)
Stats: It's pretty frail, but that speed and special attack are just great. Physical attack, while overlooked, is no slouch either so it's very easy and effective to go mixed. Additionally N's Zorua comes with 30 IVs in every stat, to help it overcome some lacking base stats in Defences and further increasing offensive potential.
Typing: Dark Type is very good endgame, between STAB and psychic immunity it's quite useful. Mid game coverage is also quite good, even though it's mostly neutral. Just watch out for Fighting types.
Movepool: Small but precise. Teach it Snarl, Zoroark's special attack makes up for the low base power and the special attack drops are very helpful to teammates. Foul Play, Night Daze, Dig, U-Turn, Flamethrower, and possibly a boosting move are just about the only other moves worth using, but you rarely need more with Zoroark, but if you're willing to get the BP Hidden Power is also a very viable option, especially since those IVs mean it will always be fighting type which has amazing coverage with Zoroark's Dark STAB and plays off of the stronger special attack stat.
Major Battles: Zoroark is an interesting case, other than Skylla's Swoobat, Marlon's Jellicent, Colress's Beheeyem, Ghetsis's Cofagrigus, Shauntal, and Caitlin Zoroark isn't an obvious choice, but through smart use of Illusion a Zoroark can easily win battles where it would be expected to struggle. U-turn, special attack drops from snarl, and Psychic Immunity only add to the utility illusion gives. It should be noted that Zoroark is not a sweeper, and should usually U-turn out once Illusion is broken (but that can take longer than one might might expect depending on how Illusion is used).
It's fairly easy to beat the Pokemon League (other than Iris) using only a Zoroark and a Fighting Type.
Additional Comments: Being owned originally by N, Zorua will gain experience much more quickly than other pokemon, further adding to its usefullness. And I can't express just how essential Illusion abuse is to using a Zoroark. You'll definitely want a fighting type when using a Zoroark (But fighting types are so useful, you have one anyway) and ghost types generally work well for illusion.