This can even be used to *recognize* your opponent's Zoroark in some situations. If you see your opponent send out a Tyranitar, the only abilities it's allowed to have are Sand Stream or Unnerve, but both of those abilities happen to broadcast themselves immediately (except in the case that it's Sand Stream but sand is already up at the time). If "Tyranitar" shows up outside of sand and doesn't give off an ability popup at all, that's sufficient information to deduce that you're really looking at a Zoroark (or Zorua).