So.. back when Tahm Kench was first released. He had a horrible early game and a better late game because of the % max-health damage on his ultimate scaling tremendously. It was compensation for the abusive laning phase that Tahm suffered until after 6. It was eventually nerfed from 8% to 6% because a support dealing 200 damage per AA was a bit strong in the late game.
However, after the rework (where his % max-health damage was moved from his ultimate to his passive), his early game has become much better, but his late game has become abyssmal and here's why:
From the levels of 1-10, each autoattack only gives 1% max-health damage per stack. At Lv11-15, it gives 1.25%. At Lv16+, it gives 1.5%. As the game progresses, others passively gain MR or buy MR items, making this slight increase in percentage not enough to counterbalance the growth, which is why Tahm Kench drops to a 43% win rate post-35 minutes (be it top lane or support).
From playing many games of Tahm Kench Top/Support, I believe that this damage needs to changed for the following reason:
1) You need stacks to be able to deal even the slightest amount of damage. Back then, it was 6%. At Level 16, even with 3 stacks, you only deal 4.5% max-health damage. Although it is also applied on Tahm's abilities, his damage abilities are on a 6 second and 14 second cooldown with 0 CDR, meaning that it barely matters in any fights since you'll just get 1 of each ability off.
2) Tahm's glory days are in the early game (0-25 minute mark) and as a support in the Ardent Censer meta, it rarely gets these types of fights unless he's roaming (which is harder pre-6), so he ends up wasting much of his strong point and becomes weaker and weaker.
It's so weird for the percentage to just sit at 1% for 10 levels (Lv1-10) and then change every 5 levels (Lv11-15 and Lv16+) afterwards. I would recommend the following:
Lv1-5 = 1% per stack
Lv6-10 = 1.33% per stack
Lv11-15 = 1.66% per stack
Lv16+ = 2% per stack
Another possible flat out change would just be change it to:
Lv1-5 = 1.5%
Lv6-10 = 2.5%
Lv11-15 = 3.5%
Lv16+ = 4.5%
This also would solve the problem of getting stacks in teamfights to be able to deal damage (before 3 stacks, you deal negligible damage) since it no longer bases the damage on stacks and is still worst than the 6% before the rework so people shouldn't complain about it too much.
**Side note: **Tahm should be able to apply stacks onto Dragon, Baron, Red, Blue Buff, but not be able to devour them. They are insanely hard to clear in the early game and not being able to eat them but increasing damage would be a great bone to us Kench bakas.
This would still be balanced because in order to achieve Tahm's former damage, you still need to apply 3 stacks in order to do so, so the damage would not be too extravagant in team fights, but also allow Tahm to scale slightly better than he currently does.
The intention of the rework was to make Tahm a most consistent champion overall, but I feel that keeping the % stagnating for the majority of Tahm's early game, when he shines the most, is actually counter-intuitive to the intention of the rework. Yes, his early game is great now but his late game is absolute crap (it's just a swap between the old Kench which had a bad early game and good late game). My suggested change would leave Tahm in a better place (he averages a 47% win rate), but not to a point where he would be omg one-shot master yi pls nerf.
In short, I would like some consistency with Tahm Kench when it comes to his place in the game, regardless in early or late game. Let me know what you guys think!