New game mode: The three clans

I was wondering what would happen if Riot created a new game mode that made it able for there to be 3 teams instead of 2. Maybe it could be on a new map, like maybe the Freljord, since the lore for there has 3 clans. I know it would probably take a lot of time since it will be making a whole new map, but you could also maybe make this game mode available on the crystal scar. I just think it would be really cool to be able to see 2 enemy champions fighting, then just jump in and pick up a double kill. And when you shut someone down, just your team will get the gold. This is just an idea that I had, and it would be cool if I saw this somewhere.