Who is the Best Hero?

I want to know who is the best hero in your opinion.

The strongest hero who is your best in your hand. Every champion is strong, but the question how much time do you need for learn like a professional LCS player. For example: I am good as support, so I am playing almost always in ranked games as support, my favourite is morgana/karma/leona, because I love damaging, but also deffend my team.

Overall the best option what you want to learn. I think in this meta the strongest champs for example trynda, panth, talon, zed and others. Most of all the meele combat champs who have jump/dash or toher thing

Pretty much what I think k8k99 was getting at- you first really have to figure out what your preferred playstyle or role on your team is. Once you've got that figured, then you could start looking at the champions generally considered as primarily suited to that role and figure out which oneyou like the most. Ultimately, playing a champion enough to get a solid grasp on what they can and can't do goes a lot farther than just trying to pick what the meta currently considers the "best" hero for the moment.

As for figuring out which champs are strongest in certain roles, there are plenty of sites out there that take and compile match data so you can compare things such as win rate, pick rate or ban rate and get a feel for how each champion currently is doing in the meta.