Hi every one, I play as Rengar in ranked games and i found out this awesome assassin build :D
Ill tell you how to use it and what is your role
1. As a jungler you need to gank alot and care about your top lane
2. in ealry teamfight try to atack the ad-carry or the support
3. in mid game use your ult to atack the strongest and the most dangerous char
4. when you push use your Q on towers get them down faster
5. at end game when the weak are running away from the team fight use your ult to chase them down and kill them

As a jungler u start with a Cloth Armor and 5 potions and go to the Wraiths and ask someone to pull the red golem use your Q all the time and by lvl two take W then use full Full Ferocity to gain HP go too the Little Golems and then gank Bot. After that go back to Wraiths and gank Mid,
then go too the Wolves and then too the Blue golem [if needed give it to one of the teammates] use smite on the golems and gank top. you supposed to be lvl 6 by blue golems and use ult to gang Mid. you can Recall when ever you want, i usually recall at lvl 4 but you can recall even at lvl 3 or 6 its up too you.

Wraiths> Red Lizzard> Little Golems> Gank Bot> Wraiths> Gank Mid> Wolves >Blue Golems> Gank Top.