I'm wondering what are the most difficult champions to play with? Which one of them are worth the effort, too?
I vote for Anivia. If played by an unskilled player, she can do more harm than damage. Wrongly placed walls are the worst, but bad skillshots (that big chunk of ice) and not knowing how to combo her spells are also awful.
For some reason, I play her extremely well (almost never die) even though she is considered a very difficult champion. And I fail at some much easier champions, for some reason.