Fans had been asking Blizzard for a vanilla version of World of Warcraft for several years now, and for a while, they all played on unofficial versions. In 2016, Blizzard shut down the most popular classic server, Nostalrius, causing widespread anger among World of Warcraft fans who missed the game they were playing 10 years ago. Other unofficial classic servers have popped back up since then, but this marks the first time that Blizzard is taking on an official version of the project.