Let's make champions needlessly complicated!
Just stay in their theme but think of mechanics that would be waaaay over the top for Riot to even consider them! Or maybe just unusual stuff, whatever!
I make the start: Orianna's passive and her basic attacks was considered kinda weird. I mean, she's litterally throwing parts of herself... kinda disturbing, if you ask me.
That is why her basic attack gets replaced by her Q, using left-click on the floor now moves the ball, the inital cooldown being one second and is reduced by buying CDR.
This opens up a new ability slot for her Q to give a new command -> Command: Cannonball: skillshot fired from ball position: ball shoots into the direction and knocks the first enemy champion hit into the direction. Enemies crushed into a wall are stunned.
