World of Warcraft Classic lets you play the game as it existed almost 15 years ago, upon the release of the 1.12 "Drums of War" update. Blizzard says it considers that era to be the correct balance of the game resembling its original launch state while also having ironed out some of the rough spots of launch. This version is also including some updates under the hood, like modern server infrastructure and Battle.net social features.
Along with revealing the WoW Classic release date, Blizzard also listed plans for both a beta and stress test of the game. Players who opt-in for the testing on their account manager page and have an active subscription will be randomly selected for the beta starting May 15. Then the developer will have three stress tests where players can log in to play the game for a short period of time on the following dates: