It's that he instantly kills things from stealth with essentially no warning, which results in his kill combo having no real counterplay.
Stealth + massive burst is not a healthy combo. Evelynn was nerfed for it, Rengar should be too.
Hugify4 votesIt seems that the community thinks nuking=toxic
but tbh Nukers minus Leblanc and Annie have fair counterplay.
Lt Cuddles4 votes
This guy can get in, kill you, and get out all in the same second, but 
can't go anywhere without ult, or brush, or summoners...
This prick here can not only stealth, but gets a crit and a blink all on just his Q while also dealing more damage to targets he hits in the back, and spawning in a clone that can do the same.. Rengar just deals increased damage on Q, it isn't a crit, he can't blink in and out of fights at will, and has 0 damage steroids outside of Q or items.
Another instance of an assassin with a clean engage-kill-disengage pattern in his kit, Talon is so well rounded in this that there isn't much reason to pick anyone else for your stealth-assassin niche: he has great damage, and strong and easy to use combo, and can blink in on E, kill a target, then escape on ult, you might take Rengar over Talon for the bola secures, but thats really it.
Oh, and did I mention that they can all instantly stealth, and Rengar can't? Rengar can't escape for shit, use that...
Variks the Loyal4 votes[{quoted}](name=Lt Cuddles,realm=NA,application-id=3ErqAdtq,discussion-id=EiFxaXKE,comment-id=0004,timestamp=2015-09-08T14:37:02.356+0000)
Oh, and did I mention that they can all instantly stealth, and Rengar can't? Rengar can't escape for shit, use that...
What this guy said.
Most Assassins can use their basic skills to Assassinate, saving their ult for emergencies. Rengar's Assassinating is reliant on his high CD ultimate.
Lt Cuddles1 votesFeels bad man...
Legendary Albert3 votessmart players buy pinks, always have a pink and when you see the ping above your team heads, put it on the ground.
problem solved, I never had problems with Rengar, sorry..
Agidyne2 votes
SEKAI2 votesSo you would rather a stealth tank?
The point of stealth in the first place is to pick off someone when they don't even see it coming, there is nothing wrong with that.
They only need to make insta kill harder to execute perfectly by giving the champ's damage some conditions to have it work out.
Stealth is no sin.
Miraweave1 votesSo you would rather a stealth tank?
The point of stealth in the first place is to pick off someone when they don't even see it coming, there is nothing wrong with that.
They only need to make insta kill harder to execute perfectly by giving the champ's damage some conditions to have it work out.
Stealth is no sin.
Stealth with a kill combo is fine, but that combo needs to be drawn out over a few seconds or the champion just has zero counterplay.
Evelynn, for example.
Stealth combined with the ability to instantly kill someone isn't balanced.
YUP
0zymandias I1 votesYou're right, riot even considered rengar being an unhealthy champ you should look it up beause his kit is just unfair and poorly made.
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