Hi, my name is InfinityCarlis2, and here is my build for Rengar - the pridestalker
This is my first guide and i hope you guys like it so... let's go!

My Runes are focused on damage just because as i play Rengar, i go for a less tanky build and a more AD focused, i have armor in yellows for jungling (yes, i start with boots in jungling, just ask for a little of damage on red, go to wraits, golems, wraits, wolves, blue, and you are done, if you prefere to gank at any times its with you ^^) and attack speed just for a bit of "faster" damage.

I go on a 21-9-0, as i said earlier this is a more ofencive build, 21 for the damage and 9 for a bit tanky, simple as that.

I start with boots and potions, the earlier movemente speed its really good because of thouse lvl 2 ganks and as many other jungler start with cloth armor and potions you will be a faster runner.
Why boots when jungling? Exactly because Rengar is a great ganker, but when he has he's ult, the only good way to gank with Rengar is to way 'till the lane is pushed or the enemy is near a bush.
Berserker's... gives you AS as supposed and more DPS since your will be focusing damage and not that much tankiness.
Rush trinity force for the damage, health, speed and for the damage sheen gives you.
Bloodthirster with your Q's passive and the AS from berserker's and trinity is going to restore a LOT of health back letting you survive those damn teambattles.
Frozen mallet for a bit more of tankiness and Guardian Angel for armor and her awsome passive :D

Max your Q's firts as it is your main damage sorce, then your W for some cool armor on fights and the life regen at 5 stacks of ferocity, and then your E, for the nice slow to secure those running kills.
Level your ult whenever it's up.
(Dont be afraid to use your ult to check if enemy's are near you or something like that, at level 3 it's a 50 sec CD more or less so dont be afraid to use it!)

Flash and ignite for the obvious reasons, one to run away or to secure a kill, and another to stop OP ult's (yes i am talking about you MUNDO!) or to secure kills ^^

Pros:
- Fun to play.
- High damage output
- Good sustainability with W's ferocity
- Great escaping with ult

Cons:
- CC owned
- Oracle's mess your escape
- Depends of team skill

Thank you if you've read this far!
Don't forget to leave a rate and coment, hope your Kitty gets better, or more Awesome!
Go get those trophies!