Easiest champion to get an S with?

Tahm Kench certainly has to be a contender. Half the time when I get an S- or above I just kinda...

https://media.giphy.com/media/cBYiHsSdCfOCY/giphy.gif

Seems like with how low his win and play rate are that the bar is set astronomically low. It feels like, unless you play horribly, you're guaranteed at least a B or above. Too bad Riot doesn't give out multiple chests per champion per season, because I'd be swimming in chests by now as a Tahm Kench OTP.

Who else do you find especially easy to get an S with?