One of my recent worst experiences was that I hovered Wukong for jungle and the Nunu on our team intentionally banned it.
Seeing that he was hovering Nunu and the horror stories I've heard of Nunu trolls intentionally screwing over their team, I had a gut feeling that this guy was going to troll us.
I was right.
The Nunu started the game charging down mid and gave the enemy first blood. I try to leave the game to try and give my team the option to remake since it had not reached the 3 minute mark. I figured, why should my allies have to suffer for his crap?
It didn't work.
I get back in game and, to no surprise, the Nunu has fed even harder in my absence, on top of which, he builds only mobility boots (typical feeder build). I figure we can play through and have the guy 9x reported for his behavior.
I was wrong.
The enemy team gets all chummy with the nunu and start sharing jokes and how they would rather report me for my attempt to save my own team from a devastating loss.
The game ends, we lose, and the enemy thresh has a friendly chat with our nunu and invites the troll to duo with them.
I report both asshats and am on tilt for the rest of the day.