Avoid as Teammate
On multiple occasions has me and my friends had a complete and abusive troll on our team, game ends and we all report them. We then queue up for a game and get the same dude on our team again. This forces one of us to dodge the queue, putting the short term damage on us, not the troll.
Overwatch has this function, do they own a patent or something? why hasn't this appeared on League yet?