My favorite way to farm with Rengar is to go in the bush let your minions do the biggest part of the work, And when you see a minion you can kill jump from the bush kill it then go in to the bush again and jump out to another minion and keep doing that because then ur enemy probably will be afraid of you and feel that he has no controll of you and you can attack him from the bush any time so he will back. Use abilities often when you farm to stack ferocity but stay at 5 ferocity then you can attack your enemy to easy finnish him off.

With Rengar you can easy feed yourself on the enemys ad carry atleast if hes not feeded.
Do like this Use your ultimate when it is teamfights the ad carry will stand little behind the fight use ult and run to the ad carry but dont jump on him until the ultimate has stack up 5 ferocity then jump and use savagery (your Q) 2 times then bola strike then u should have killed him.

I recomend that you take ghost instead of flash cause you will need it sometimes when you use Thrill of the hunt or you just take flash it does not really maters they are good on diffrent ways but i recomend ghost on rengar and exhaust so when the enemy run when you attacking from the bush you can slow them little extra so you can get in some extra strikes before he gets into turret range.

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