Years of changes, reworks and reverts later LeBlanc, Rengar and Fizz are STILL fundamentally broken.
I've been here for almost every single change to LeBlanc and started playing before Fizz and Rengar. Hell I named my cat Rengar right after his release. At no point in the history of league have these champions felt good to play and good to play against. It might be time to admit that you cannot balance their current play styles.
Probably needs to be reworked as a skirmisher with an extended play pattern of engage/disengage instead of an assassin. Making him a healthy assassin would require removing or reworking his passive, Ultimate and Troll Pole to the point where it alienates Fizz mains.
Needs a massive overhaul including but not limited to a real ultimate with a real cooldown.
Either needs a massive rework to all abilities to be a healthy assassin or needs to become a skirmisher instead.
We can keep nerfing and buffing these champions and continuing the cycle of abuse or we can actually make major changes and fix the bastards.
seem to fit right in-between these two roles, so they should probably be able to dive in and kill a target at around 50% hp, but they should have a harder time disengaging and should have less map control than a more pure trickster assassin (who shouldn't be able to duel) like Shaco, Leblanc, and Evelynn.
interaction, but that's a problem of its own that affects multiple champions.
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, and
. This allows him all of the burst of an assassin and minimal (if non-existent) risk that comes with it. If you really want to nerf a champion, remove their utility.