Challenge: Can anyone explain to me how Lee Sin is OP?
I understand win rates aren't everything, but: Lee Sin's win rate (being generous and rounding up) is about 46%. (This number does not rise appreciably in Platinum/Diamond.) There are six champions with win rates worse than Lee Sin: Zilean, Evelynn, Kha'Zix, Elise, Kassadin, and Bard. Lee Sin is tremendously more popular than these champions, which presumably takes his win rate down a bit, but usually such effects don't amount to more than maybe 2%. And although he sees some pro play, he is by no means dominant at that level (generally Vi and Rek'Sai are preferred to him).
And yet I see a lot of calls for Lee Sin nerfs. And I just don't get it. The fact is, Lee Sin's strength is defined by a pile of numbers (base and growth stats, base power and ratios on his abilities, etc.), and for some values of those numbers, he will be underpowered; for others, balanced; and for others, overpowered. And I just don't see Lee Sin as being overpowered.
Could it be that the folks who want Lee Sin nerfs just don't enjoy playing against Lee Sin, to some extent regardless of his actual power level? (If this is you, what don't you like about him?)
is overpowered, rather, he's overloaded and balanced around that (hence the low win rate). He's been made statistically weaker over the years, but his core issue is that he still has so many mechanics that he doesn't really have a real weakness to exploit on a play-by-play basis (as opposed to him falling off late-game, which is itself mitigated by his always-useful utility and Insec kick capabilities). Because he's so versatile, adaptable and historically popular, he's pretty much the default pick for a lot of junglers if they're not sure what to do, which until recently has been crowding out a lot of other junglers. He doesn't need any nerfs, but he does need to have a genuine weakness besides poor scalings, which would allow him to receive significant buffs elsewhere. It's also why it's difficult to change Lee: changing him would involve giving him a gameplay niche, and therefore specific strengths and weaknesses, but his defining feature right now is his extreme jack-of-all-trades effectiveness, so Riot needs to form a very clear idea of what they want to bring out in Lee before doing anything to him.
