Remove the tank role, retool all tanks into utility casters.
Might as well. Riot has some kind of legitimate problem with defensive gameplay. They've stripped tanks down enough that the only viable tank who doesn't get melted instantaneously by any given ADC used to be Ornn. Then they broke him. I come back after some time off and realize that Riot wasn't ready to step outside their box and steal that particular idea from HotS yet. Yes, that one. The invulnerability.
It had a short window and was skill-based. You needed to time it right and pick your moment for it to be effective. You could fuck it up. What was wrong with any of that? Without it, Ornn is pretty much useless. His shield is mediocre, his speed is garbage, his dash range is too short to be a good initiator, and his slow is unreliable and underwhelming. Sure, he does nasty damage against brittle opponents, but he can't risk getting close enough without the ability to cancel out their CC.
Shame on you, Riot. Shame on you for breaking such an interesting character to the negative, while allowing AD champions to run roughshod over the game with their imbalance. (Don't believe me? Play five solo queue games. Tell me how many AP champions you get on both teams between those five games.)