Your Win Condition
You are favored level six to thirteen. The goal is to E-Flash him when he is out of the bush.
General Strategy
Rengar Top wants to sit in bushes and control the lane. Try to stay away from the bushes entirely. Rush Black Cleaver with Kindlegem and Long Swords.
Trading Patterns
If Rengar auto attacks you while you E, you can use your shield to block the damage and flip him. If Rengar uses his empowered W, it is a cleanse and will allow him to cleanse your R2 execute. When Rengar ults, stay away from the bushes. If Rengar is about to jump onto you, it is guaranteed for your E to land.
Wave Management
Their Win Condition
Rengar wins by utilizing the bushes and cleansing your R2 with empowered W.

