The Zed nerfs were confirmed to be for more counterplay

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by late game his R is useless always. What counter play do they need? Aps rush zhonyas and adcs rush QSS... tanks just stack hp and armor. its about the easiest shit to counter play especially since on AP item effectively negates it.

Zonya's counters a lot of things in this game. Infact, almost anything. Zed relies so heavily on his deathmark that using Zonya's against it really mitigates his damage, and the armour that it gives counters him pretty well too. Though Zed is still an effective assassin, the fact that most APs rush Zonya's regardless of lane match-up (and will certainly when they see a Zed) means that he isn't effective for too long in lane. QSS is a little bit different, since it does greatly reduce the damage of an ADC who builds it, and ADCs that itemise defensive items anywhere before their 3rd item will be much weaker than the opponents. But Zonya's still gives 120 AP, so yeah.

Supports have a lot of cc, I wouldn't ult a support :P