League-of-legends – Which champions have abilities with reduced cooldown on ‘failure’

Bonus health means health gained from items / runes / masteries.

At level 18, Shen naturally has 1958 health*, so Ki strike bonus damage is equal to (Total Health - 1958)*.08.

*Shen suffers from a reduction in health due to the Inverse Ninja Law when Akali, Kennen, or both are on his team. This will reduce the base health of all involved by 1 or 2, giving Shen a range of base health from 1956-1958.

The short answer is no. You are always in a better position if you are using a champion whom you are good at playing.

If you pick a counter you are not good with, you will have to try and adapt your playstyle to a kit you don't know, create an item build path you haven't used and played with before, and try to figure out exactly "how" your kit counters their kit.

For instance, someone picking Talon mid vs a squishy AP mid would be at a serious disadvantage if they didn't understand how Talon's burst combo should be used. If you go in on Brand with no understanding of how to quickly get Talon's damage in before Brand can start his combo, you will die.

tl;dr: If you are trying to counter a lane, rely more on your ability to play a champion well than which kit counters your opponent.