I fought a full tank Ekko in top lane yesterday.
I'm not sure what level he was (I was with friends who were smurfing) but he had grasp so I assumed he was max level. I was Sion, which normally Ekko would dance around.
He did dance, but he couldn't kill me. In fact, it looked like I was winning trades the longer they went on. After rushing visage, his attacks didn't do enough damage to really hurt me and his lack of MR made my E and sunfire hurt more (tip for you "tank" assassins. Counterbuild your opponents main source of damage. Don't just put on "OP" items and expect to face roll).
Riot, you did a great job with the tank Ekko nerfs. He was still annoying, but he wasn't a massive damage threat.
I hope you can fix the other "tank" assassin builds as such.
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, he would have no problem. Having a tanky Ekko just means that kill him would be more annoyingly difficult. I won't doubt that the changes made to Grasp and Ekko made a bit of a difference, but Sion is just as hard to take down as a tanky Ekko (if not, harder).