WoW's 12th Anniversary

WoW's 12th Anniversary is a Feat of Strength achievement earned for logging in during the 12th anniversary of World of Warcraft between November 16, 2016 to November 30, 2016. Everyone who logged in received a Anniversary Gift (old) in the mail, which contained:
 * Timewarped Badge x200
 * Letter from the Timewalkers
 * Celebration Package