Hi im a euw player of league of legends. I love playing rengar even after the rework.
I'm silver 4 and I played only 1 season so dont take everything too serious.
I hope you learn things in this guide please comment if you did.

+ fun playstyle
+ pretty easy too play
+ wins games if ahead


- if behind you are weak
- can mess up since you Q is a skillshot

Before the assassin update rengar could easily, even without a leash.
Now clearing your jungle withour a leash is pretty hard but its do-able.
usually take red buff first; im standing in the bush so greenfather gift will be used i try reseting my autos with Q. I take W first since it wil heal you for the damage taken last 1.5 second and go to raptors this camp will almost kill you so make sure not to activate W when you jump into raptors wait 1.5 seconds to heal you most. Go for scuttler and go intuitive now since the hardest part is over.

So there is a botlane that does no see you coming. Ask your support to check for control wards (R.I.P. pink wards) you activate Edge of Night then ult make sure not to come to close becous they will be seeing you then. Walk that way that the squishe target is closest so you will be critting him then Q E basic W Empowered Q and Q smite if they dont die.
When casting Q out of cast range you will do a little hop so you can Q when they are not in range. Well now you know how to handle bot lane you can use this all game long even if its not bot lane.

So This is my first guide i hope you liked it. Comment if you lake to share thoughts.