Maokai is the rampaging tree. He brings a lot of crowd control and plenty of damage reduction to a team. He’s picked, primarily, for power, not for any broken op reasons. He’s extremely strong in lane due to his sustain, wave clear and dueling potential. He brings a ton of cc later in the game, as well as AoE damage reduction. His damage isn’t anything special, but high enough to be a decent threat in lane and kill people later in the game.
His identity is really that of a cc tank. Beyond that, he brings the special ability counter AoE damage abilities pretty heavily because of his AoE damage reduction ultimate. Focusing on those two things are primary when looking into his power levels.
His strengths are his sustain, wave clear, crowd control and general tankiness (partly due to his sustain). His weaknesses are his lack of damage and mostly short duration soft cc – the snare is nice and 2 seconds at max rank, but most of his spells are more for momentary disruption and decent chasing power. His engage range isn’t anything to write home about, and he’s much better at countering an engage. He needs to get off auto attacks over the course of a fight to make sure to make use of his passive.
1) Focus on his unique identity of “team damage reduction” by reducing his own natural tankiness. Maokai is naturally extremely tanky because of his sustain and ultimate, but I think you could reduce his tankiness while keeping his identity by reducing the base and growth stats for armour/mr and increase the damage reduction slightly on his ultimate. This makes him a little easier to poke at and duel in lane (making him not as much of a brick wall) and pushes him to focus on his identity, rather than just popping his ultimate and just becoming a monster tank that ignores the benefits his ultimate brings to his team.
2) Reduce the sustain from his passive. This could be done either by reducing the actual number (from 7% to maybe 5-6%), or by increasing the necessary charge count to obtain the passive. For the former, this is a straight nerf to his tankiness across the board, so I don’t love it – I want to keep him powerful later in the game, where he should be making use of his team fight strength with his crowd control and ultimate. Increasing the charge count, however, is much more significant in lane than in a team fight. In lane he can pretty much activate his passive the second is gets charged, while in team fights he’ll usually have a few charges lost between his auto attacks simply because of the number of spells going off. This means his ability to maintain charges in a team fight should remain about the same (perhaps a small reduction), but the requirement in lane will be more significant because there are less spells flying around to charge up his passive.
3) Straight up reduce his damage. It’s not really part of his identity, so hitting it wouldn’t be so bad. Damage reduction is usually just about power nerfs, and that’s more or less exactly what this is. Basically it would reduce his dueling power in lane and make it a little harder for him to assassinate priority targets later in the game. Pretty meh on this one, although I wouldn’t be surprised to see something like a small damage reduction on his Q go through.
Essentially, most of these nerfs are targeted around making him less of a brick wall in lane. I think reducing his laning power is probably the way to go.