Some forms of trolling are undetected/go by
So in the lobby, we had two people fight over yasuo. One of them asked and said in chat
Troll: "Can I have yasuo? IF you don't give me yasuo. I am going to fuck shit up for you guys"
Yasuo: Nope I'mma play yasuo
No one dodged and the game commenced, so the troll went on to play teemo.
Then Teemo (top lane role) went into mid and stealthed/sat there, then started to talk to our yasuo.
Now the important part is that he did not talk "derogatory" or "expletives". He just kept talking about random stuff. You know, stuff that would avoid the automated ban system. But obviously staying in mid and leeching EXP and talking to the team tilted EVERYONE.
I'm pretty sure everyone reported him - but he didn't get a ban. Why? Because he just took kills when he could and he didn't feed. But he sat in mid lane and just sat there stealthed. ** Unless this game gets manually vetted, he's gonna get away with it.**__