I never drone scout in ZvZ, even if I go hatch first. If I get early pooled then well played, if you don't then my risk paid off. Your lings and overlords can see everything, even if they're not in your opponents base. See lings before your pool is done when you went 14/14? He early pooled. See nothing come out of your opponent(if your overlords passed by or something) when you have lings half way across the map? Hatch first or roach rush. ZvZ is just a game of knowledge of timings and styles. You will get all your information off of the way he spends his larvae.
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