PvE Gamemode

So with the release of the rotating game mode, everyone has been getting variety in game modes. Even so, I feel as if a Player versus Environment mode would be a really cool thing to have. Imagine teaming up with randoms to fight off waves of void creatures, Noxian or Demacian soldiers, bilgewater pirates, or other minions. Just to fight a boss at the end. The map wouldn't even have to be that big. I feel like it could help build teamwork and reduce toxicity since you're not really playing against people.