Kayn is my new jungle PERMA BAN

I have had bad experiences with kayn lately and I want to see if its just me or if he really is broken in other peoples games

There was a time when I could stomp on every kayn I saw but now he will carry every single match just because his movement speed and life steal

I actually dont know how its possible often times how he can pull off such incredible plays then be at full HP .2 seconds later

If you guys also have any advice on how to counter play kayn I would love to hear it because he is something I have a hard time dealing with