Karthus rework.
Karthus has one of the lowest pick rates in the game. He's one of the champions with the lowest play rates in the game.
I used to main him, and he was a lot of fun.
He was kind of a xerath before xerath existed, but both the AP ratio and the cooldown on his ultimate have been nerfed repeatedly over the years.
Frankly, I kind of understand why, because having the level of AP ratio and cooldowns that he did at the time made things kind of nuts.
But now, he's pretty broken the other way.
Sure, he has a nice niche where he's a good counter pick to teams that will be doing a lot of diving and you can use the ult as a deterrent and kind of shut them down when they get too low.
But you can't use him like I used to, and before anyone starts no, I'm not talking about spamming the ult during a team fight.
I'm talking about sniping that one cocky player on the other team every time they do something stupid.
As karthus I exploited mistakes and weaknesses in the other team. I was the sword of damociles hanging over their head waiting for them to make a mistake.
When that Garen burned his TP to come from top lane to bot to try to gank and chased past both towers and then hit teemo's mushroom? Karthus was there.
A minute and a half later, when yi initiated a dragon fight at less than half health? Karthus was there.
As a main Karthus player for me, the point wasn't that karthus' ult could hit the entire other team and potentially skew a team fight.
It's that I could hit that one other player anywhere on the map, almost anytime.
My ult had a cooldown comparable to Ezreal's and if you made a tactical error, you paid for it.
I've played LoL off and on since season one, and recently I was thinking about how to address both the legitimate reasons for the various karthus nerfs, and (in my opinion) to allow his ult to function a bit better.
One thing that struck my fancy was the way Kindred selects a target for a hunt.
One idea that I had was to either make the karthus ult single target or an AOE ability centered on an enemy champion, and simply have a box for selecting the target above the R button much like kindred selects the targets for her hunt.
You could probably even re-use some of the existing UI work and code from kindred's passive for it, and then you could pretty easily re-work Karthus' ult to have a more balanced cooldown and AP ratios since it wouldn't automatically hit every single enemy player on the map.