>>43727356The biggest problem competitively is Team Preview, it just leaves your opponent thinking about when Zoroark is going to come into play. I think it would've had a potential niche if Zoroark had a mega back in Gen VI; one implementation could have either it mega-evolving while disguised and then getting a new ability as usual, or simply becoming a mega in complete stealth.
But since that train has long passed, if Team Preview is to stay then just have a honest-to-god buff to the ability and a moveset improvement will help. Maybe another typing or a good hidden ability to pick up too?