[Rotating game mode concept] Welcome To The Jungle

This game mode would function a lot like a cross between Summoner's Rift and ARAM.

The Rift isn't what it used to be. After centuries of neglect, Top and Bot are massively overgrown, and have been claimed by The Jungle. Only the mid lane turrets and inhibitors still function at all.

Monsters have all grown in power, and they hoard greater quantities of gold and experience. New camps exist within the ruins of Top and Bot lanes.

How have the mid lane turrets stood for so long? Ah ha, I see. The Elder Baron is protecting the mid lanes for some reason. The Archdrake as well. Both of these Epic monsters are stronger than in centuries past.

The mid lane turrets are invulnerable except when attacked by a champion who has an epic buff or is standing near such a champion, or when super minions are present. Epic monster buffs are transferable by kills. _ (Remark: Please be kind if you have a "Simpsons did it" remark. I Googled briefly and didn't find anything already proposed along these lines.)_