Porting Back To Base
There was a hack in a game I played in where the person I was laning against, a Kha'Zix could teleport back to base instantly whenever he chose. And it wasn't his ultimate, I know the difference between Kha ult and just disappearing completely. It was impossible to play against, and I hope Riot has a plan to address people using this hack very soon.
EDIT:
https://www.youtube.com/watch?v=q_L79YhHMOA
NOT My game, but this is exactly what I'm describing, for those of you who think I'm just making stuff up.