Some things which might improve your Tahm play

1. MS quints dude, MS quints are OP. So good for proccing your passive, get them MS quints.
2. HP seals are overrated, get armor seals and armor marks too (MPen marks work if you're going to be poking the enemy a lot and you know you'll get to poke a lot). The low amount of HP that HP seals give aren't worth the slight amount of damage they give on your R, armor helps you overcome the (usually difficult) laning phase, especially against an annoying matchup like Lucian.
3. Your W screws over just about every assassin, so please keep it in teamfights if the enemy has an assassin. Hell, after you eat your carry who just got death marked, throw a few laughs at the enemy Zed, he'll probably tilt.
4. About your W: your first instinct when using it in a teamfight is probably to spit out the enemy and do your damage straight away, but if you have an important carry locked up, it might be smarter to keep them in there and wait until your team deals with the other people. The lockup lasts very long, and people honestly underestimate it.
5. Remember to always spam laugh to establish dominance and tilt the enemy.

That's all folks. iI you have any questions, feel free to ask.