Originally Posted by Xelnath
I think it's a valid complaint that his jungling is on the weak side. He lacks super hard ganks and even Dekar has a rough time jungling with him.
Do you think thats because the jungling role doesn't give him the opportunity to snowball the way toplane does - or is it something else like his slow initial clear speed?
It's his clearspeed, for sure, and he's incredibly vulnerable to counterjungling. Rengar needs to be able to do a lot of damage to be effective, and he just can't if you build him so that he can jungle without getting owned by creeps. I've jungled him a lot less than I've played him top lane, but I pretty much have to go 9/21/0 not to get destroyed. Again, that leaves him without high damage output.
You also have to build him in a way that doesn't exactly play to his real strength (as you can in top lane), which is to build bruta, kindlegem, tooth. The Dekar build makes him viable -- CDR, damage+pen, early health - it gives him just enough damage to get himself fed, enough CDR to sustain/survive lane, and enough extra HP to live through a little bit of punishment. His jungle build path just sets him too far behind.
Because of his early jungle, his ganks are late compared to other junglers, and are less effective unless you can use the side bushes to close gaps. His level 6 ganks would be more potent if not for the weak early game and the necessity of Wriggle's Lantern to make his clearspeed not unbearably slow, although the level 6 gank is still pretty scary, even considering that you're not buillding damage.
Bottom line is that Rengar is completely useless without damage, whereas other junglers right now can just build one damage item, then convert to tanky stats and still do much more in the game than him, utility and damage-wise.
He's a very binary character right now - either unstoppable or useless. Going jungle almost guarantees that he will be useless.