Yi or Essence Reaver, your choice riot.

Rework one or the other, or lose half of your playerbase. I refuse to play against a champion that becomes untargetable every 0.5-1 seconds and at the same time does 600 damage to 3-4 targets. CC wont work on him because as i said, untargetable every 0.5-1 second. Little to no counterplay, get your entire team to focus him while rest of yi's team deletes yours and he still manages to Q+Autoattack your ADC for 90% max health damage, not to mention he might survive anyway just by pressing W and reducing your damage to non-existant while waiting his Q to get off cooldown again to keep doing those juicy 1500 true damages in 1.5 second(got to see it the hard way as 4000hp+300armor rammus). So yeah, make your choice or feel the cries of all people from bronze up to diamond. [slayer-pantheon-popcorn]

Edit: Since this post also gets downvoted to hell by yi fanboys with no descent arguments, ill post a link to another similar discussion that has few upvotes and support with valid point arguments. I think they might have explained this a little better than i have:

https://boards.euw.leagueoflegends.com/en/c/champions-gameplay-en/ZjowEBZO-master-yi-s-true-damage

This is more regarding to his true damage but it's nearly the same point, his cooldowns and damage are way off than it should be allowed to.