After 6.9 Jax lost his sated and guinsos and is way better as a tank now, he has good skirmish and split push power after 6 and tank with cinder and titanic means he clears fast. If you build alot of armor you can tank the turrets. In team fights wait for the other team to engage or your own and stand in front of our adc, smite there front line and beat them up. Remember your job is not to be an assassin anymore in this new meta your job is to soak up damadge ment for your adc and kill the frontline who got to far into your team.