Helmet Bro. Mode
I have always liked the legend that is the Invincible Helmet Bro. I think it is time Riot got him into the game.
Helmet Bro mode would work with all existing game modes. The only change made would be an extra player for each team is added and randomly a helmet bro would be selected for each team. What does the helmet bro do you ask? Well sit back and I will tell ya.
The helmet bro would do what he does best. Be invincible. Nothing damages him. CC still affects him. He only does minion lvl damage for autos. No skills.
The idea is that he can go anywhere and be a pain for anybody he comes across. Have him soak up damage in lane, have him pester enemy jungler, have him slowly take down turrets (turrets do not affect him either). Helmet bro does as he pleases.
Just a random thought I had. Feel free to add or take away ideas to this mode.