Kalista in Pro Play
Kalista in pro play has been OP since release, aside from when they made it so her rend took 2 targets to execute to gain the cooldown back. When that was implemented, she was never played. When they brought back the original 1 enemy execute, she became broken again. Kalista's the first ban from every team on red side literally every single game at this worlds because if she isn't banned, she's first picked. She's by far the most broken champion in worlds, and has been the most broken champion in pro play for awhile. I hope Riot finds a way to balance her for pro play, because since release she's shown she can only be ridiculously broken or irrelevant in the meta.
Q to blind for 6 seconds. He would instantly become a support because his basic ability makes another champion useless for 6 seconds. True balance can never exist in this game...unless you give every champion the same skills with the same damage...