The symptoms are already showing.
*pr0 ward jumps and shadow blinks "outplay" highlight reels 
*riot's refusal to nerf because champion skill cap justifies being overpowered
*energy :P
Did? Implying Lee Sin isn't still dominating.
I can't remember a time when Zed killed me and I thought "oh, if I had just done x, y or z I may have been able to survive that," with the exception of buying QSS against an all AD team.
That said, I don't think he'll stick around as long as Lee Sin because he doesn't look as cool doing his thing.
my problem with zed is lack of counter play, especially if you're on a skill shot based champ. he ults you, disappears for a while then returns and if you're lucky you hit him but if you're able to hit him he's hitting you again, then as you continue to try to hit him he jumps to his shadow and runs away while your only option is to stand there and wait for his death mark to either kill you or nearly kill you.
You can rush qss or zhonyas to add some counter play but even then it can be a toss up who might win and he can still run away just as easily as before. Oh and your item has a longer cd than his ult so good luck next time around
I think they should maybe change the dynamic of his ult so he's not invincible for the time he's marking you. Definiitely decrease the width on those damn shiruken, they could use the nid spear treatment
zed has remain static for ages, i don't recall any recent buff either.
We all know how big Zed's playerbase is and how delusional Zed mains are. Almost too similar to our Lee Sin problem
Welcome to Riot's only priority being #LCSBIGPLAYS and not actual balance or champion diversity.
The "op" thing with lee and zed is their mobility and their unique play style so u just can nerf their dmg but they will alyways be "broken" in a special way
He definitely needs some tuning. You can dodge every shuriken in lane and he'll still 100-0 @ level 6. I'm not that good a player but man even before that he can miss everything then shadow to you spin-spin aa and you're dead. if he has ignite the kill is almost guaranteed. And all zeds I've played against know it too lol. If you blow a cooldown or he manages to get close to you you're either dead or going to recall.
I think he's a good champion with a high skill ceiling he's just slightly overtuned. Shurikens narrowed maybe some numbers here and there. All I know is you shouldn't dominate lane against any opponent with just a long sword lol.
People who say zed has no counter play blow my mind. Zhonyas Qss ninja tabi
His level 1 ult is garbage
if you are playing mid mages here is what you do when he ults you lvl 6 and you know EXACTLY WHERE HE WILL LAND
you literally can't miss
satchel charge Force of will tidal trickster grenade riftwalk ring of frost/Frozen Tomb dark binding light binding command shield/shockwave
to name a few
People who say zed is op also just blow my mind. An assassin killing you quickly when you are out of position is ok. I play squishy immobile assholes when i play mid and i don't fear zed
zeds problem is his wave clear and ease at last hitting. gut his passive and make his shurikens do reduced dmg for each pass through or make it hit only the first unit. his dmg is fine and his mobility is stupid yet manageable, but his wave clear and cs'ing is just fucking retarded for an assassin.
there is a reason he is picked in almost every other pro game and its not because he is a cool champ.
Um yeah what are you talking about riot has nerfed zed countless times.
i see zed often but he isnt that scary for an assasin to be so peelable and having such a long downtimes on his assasinations (compared to guys like akali kata and fizz)?
he is indeed fun to play but i wouldnt call him the case of a lee sin
I mean, Zed ends up right behind you after using Death Mark, doesn't he? If you've got some form of hard CC like a stun or knock-up, you can aim just aim it right behind you when he ults and that should help mitigate his damage.
Zed reminds me of the old 
were she was super powerful but had a high skill capped, but after being out a long time many people reached that skill capped and was just broken but no one knew until people reached her skill capped. I feel zed is the same way he was always op but until people reached his skill capped he was ok but now riot needs to nerf him a little to balance him out like they did to oriana.
The first change I think he needs is reverting either the change that removed the range restriction on his ult (for warping back) or making his ult spawn a shadow behind the target, he's too safe atm. Most assassins are feast or famine, Zed is feast or do decent.
Zed winrate in solo queue: 48.20%
I don't see the problem. Professional picks are irrelevant for solo queue, and in solo queue (where everyone in this thread lives) his team is more likely to lose than to win.
Zed 48.19% winrate in solo queue.
Still a bad pick in your games.
at least zed wins games.
Zed is not overpowered. Just frustrating to play against when you are playing against somebody who is really good with him. Same with Yasuo (his buff made him overpowered, but he is now fine), playing against a good one will give you 0 chance of winning the lane. Oh you thought playing against Fizz was annoying? Just wait till you see a really good Fizz main play him. Also Zed is countered by quite a lot of stuff (but lacks counterplay other than unloading all cc on him when he ults), Zhonya, QSS, GA, Mikael, Lissandra, Kayle, Zilean, Zac, Anivia, Lulu, etc...
I'm really surprised Lee (and also Thresh) are allowed to exist in the state they are in though. Especially Lee, he has been receiving nothing but love taps for 4 fucking years. He has literally everything in his kit except invisibility and invulnerability. And Thresh is just a combination of other supports in the game by taking 1 of each skill that makes other supports so good.
There is one glaring problem with Zed mid tho. 
