One does not play League of Legends in a quest for diverse play environments. This is kind of the nature of the MOBA; you have a wide array of different heroes to throw up against one another on a very limited number of very predictable maps. So it’s all the more important that those individual maps feel fun and diverse to play on. LoL rose to the challenge with a winter-themed Summoner’s Rift, but just like any good story, it almost didn’t happen… until the team found a way to make a fast and convincing winter wonderland.
The remake of the Summoner’s Rift took the better part of a year to implement, and the understanding had been that replacing the map with a winter-themed version would require the same amount of work for something only available briefly. However, a new procedure allowed the team to isolate specific portions of the textures, which allowed for a quick illusion of snow that took weeks, not months. You can see the process in short just below and read about the whole journey on the official site.