So, I was at my summoner profile in the champion section, searching for some champs using filters (carry, support, etc..) and it came into my mind: there should be an "op" filter. You know, when you just want to search for them, there is the filter.

0/10

You need help finding gimmicky champs to counter?

*facepalm* It doesn't matter how OP champ is if u don't know how to play him.

This

And for the record, there are no OP champs only UP players

Or OP players.
Anyway, there really aren't any OP champs... although Jax is the closest to my mind

Jax isn't OP. Especially with the new black cleaver making other tanky/dps champions so much stronger in comparison.
Jax is easy to counter too. Just play Olaf, Panth, Zed, Udyr, or really anyone with a lot of ranged harass to stop him from farming and put him at low HP if he tries.

Udyr top is insanely good right now in my experience, due to the fact that he doesn't have any strong counters other than teemo, and teemo can't kill him if he doesn't want teemo to. His late game is also really strong, and he is nigh impossible to kill if he decides to run (he is the fastest champion in the game with maxed bear stance, and turtle keeps him from taking significant damage while running)

OP champs are mostly melee
when a mage champ gets too strong
they nerf the hell out of them

Melee champs tend to have a panic button or special something to make up for their low utility. They also have scaling MR. Nooblords understand niether of these concepts and come to the forums to cry foul because they gave a poor performance

And the only champion listed there would be Anivia.