Can you Install Custom Maps in LoL?
This has good and bad news: Yes, you can install custom maps in League of Legends but it will be overwritten to an original map. This means that there will not be a separate and brand new game mode when you install a custom map. This is because installing custom maps is like installing custom skins, they only change how the original map looks. Some modding teams are putting a lot of effort into this and show their creativity by making amazing works. To give an example of custom maps, you can install “Butchers Bridge” and play it on ARAM!

Other players will only see it as it is the original map but in your perspective, it is entirely different! You can use this trick not only in ARAM but in other game modes as well.