Shaco
His nerfs are unjustified. He may seem strong because of his winrate, but it's just inflated by the fact that people fear Shaco. Yes, he is not that strong, he is perfectly balanced right now if not a bit weak, proof of that is that he is rarely picked in competitive, and both times he was picked, his team lost. So people lose to Shaco because they fear him, while pros doesn't give a fuck and thus win. When people see Shaco on the enemy team, they play worse, hug tower, lose cs, lose lane dominance etc all because they're fearing that stealth gank, putting themselves at a disadvantage.
Also the only build that is even remotely close to being strong is bruiser, but the nerfs will target it the least while gutting AP Shaco that is already very weak.
Any Shaco build is vastly outclassed by other champions.
AP Shaco is nothing close to other AP assassins and burst mages. Bruiser is useless compared to proper bruisers lire Irelia and Jax. AD Shaco is dead. AS/Crit Shaco loses to any other adc, melee or ranged. Support Shaco is also dead.
All shacos are dead, those nerfs are just the final nail to his coffin, poor

as an exemple. He was strong for a while, but nobody played him until pro players suddenly picked him up several months after his buffs.