No need to phase dive onto Riot, they just need a Chronobreak.
To be perfectly honest, not much they can do if you're referring to tank ekko. That build is a cockroach, it never dies.
Here's what you do with Tank Ekko
Remove his passive slow, remove his W shield, remove his ult heal then call it a day and never look at that champ again. If he comes back after that I'd agree with you, but until then you can always gut cancer harder.
HAHAHA!
Mad jokes.
WHY AM I STILL GETTING HATE