@Riot Is it possible to get D-? AFK Master Yi connected back for merely 2 minutes and got B-. Weird.

I just had ARAM game where our Master Yi was afk nearly whole game. Didn't come early, it disconnected him and reconnected just for the last teamfight where he basically did nothing as it was nearly won. His stats ended up like: KDA 0/0/0 2 Minions 8.6k gold (by natural generating most of the time) 0 physical damage dealt to champs 0 magic damage dealt to champs 2597 physical damage dealt (to the minions I suppose.. like... okay... 'twas his Q) 208 magic damage dealt 444 critical strike maximum 686 damage taken Built Statik, Blade of the Ruined King and AS boots like ordinary carry

According to what he said in his joke-chain "izi :/" "why only b-? lel"

Since he even jested how easy was the game, despite the fact he didn't even play it, If he meant to make a joke about Mastery Grade he'd say something like "only A+? I played quite well... I deserve hextech chest" or even S grade. This way it makes me believe he actually got it. However, I don't have data to proove it.

So basically someone who didn't even play the game, just finished the nexus (If he even tried to hit it) got B-. I mean it's pretty terrible grade. But taken he didn't even play. Like... Do I need to kill my own minions and have -60 farm to get D-?

Additionally, it's funny because I as carry dealt the most damage from entire game at over 29.5k as Ezreal and had 11/10/14 KDA (which isn't really that great but for squishy buster in 5v4...), 11.8k gold contribution and got the same grade. Not that I'd be complaining, I just noticed that later for comparsion.

Note also that this was ARAM which should be having different Mastery Grading system since we waited for that thing for so long when other modes already had one.

Is it really working as intended? And you have to basically... I don't even know. Do damage to your own teammates? Make trolling as Tahm or Bard and CC your own team? Have negative farm? In order to get D-? Is it that it's impossible to get D- so that terrible players who just began playing don't get sshamed that they were worst and have the placebo feeling that someone was even worse and they are improving?

I just would like to know more.