Fizz or darius

Depends. Do you want to be that guy ? Or do you want to be THAT guy? Fizz is more of an assassin mid laner that thrives off of roaming to other lanes, but has a weak early game. Darius is probably the most notorious lane bully in League's champion roster. Darius is a juggernaut, meaning that he is prone to being kited, but if you get into melee range of him, you're dead.

If choosing, ask yourself the following? What do I want from this new champion? What champions provide this for me? Does this champion look fun to play?(Cause why play the game if you're not having fun?) And Finally: Do I just like the champion because he/she/it is FOTM, or do I just like their gameplay?

Well Fizz is kinda trash sadly lol

Depends on your play style. Fizz is better in higher levels because people learn to beat Darius you just have to not stand there and fight him. Fizz is good because has an intargetable, and more burst