Even I think tahm kench needs to be looked at...

First off, I`m a tahm kench main with 1.3 mastery points on him, I don't have any bias against this champion.

But ive watched riot power creep this champion`s laning phase over the past few years as they slowly took away his late game scaling (and utility in pro play.)

He used to have his passive damage on his ultimate, not only that but it also did % bonus hp damage, this meant even when tahm kench got a hold of his R he still needed to build hp in order to obtain his damage.

When riot took it off of his R and changed it to %total hp per stack, they made him less reliant on building hp in order to deal damage, especially in the early-mid game when he can just use his base health.

Riot has also power creeped tahm`s Q while nerfing his W, it used to have a 6 second cd, now it has a 4 second cd at max rank, getting max points on his q is his biggest powerspike and the only real one he has.

Tahm`s W damage used to be what he relied on for killing tanks/juggernaughts in the late game, now the damage was hard nerfed in favor of a much stronger q that he could abuse towards the end of the laning phase.

Infact I rarely eat enemies as tahm kench now unless its to counterplay something like a jaxs counter attack / poppy ult or I need to get them back to where I can q them again, all of tahms damage is from auto attacking + q spam.

Put his passive damage back onto his ultimate, you can keep it as %total hp per stack and have it scale with the amount of points he puts into his R..

1/1.5/2 would be a good start, tahm wouldn't get a hold of his current damage until lvl 11 which is when laning phase is usually over/ending.

Also even I was against riot buffing the slow on tahm`s Q, you are just making him bully immobile champs while keeping him relatively useless at dealing with mobile champs in the top lane, hes basically / if you just kept powercreeping their slowing slows + mobility and never gave them a ground effect.

If putting a grounding effect on tahm`s q sounds overpowered, nerf the slow and put a movement speed cap / soft cap on whoever he lands it on so he doesn't hurt immobile champs as much and hurts faster champs a lot more.

OR you could just have the slow % scale per champ level, so he only gets his massive slow at lvl 18