The 20th anniversary of the Diablo series will occur on December 31st and Blizzard plans to mark the occasion with some special events.
The special in-game events and items will not only affect Diablo III but various other Blizzard franchises including Heroes of the Storm, Hearthstone, Overwatch, StarCraft II, and World of Warcraft. Specific details will be shared soon, but the developer gave a preview of what to expect in each game:
Recapture the feeling of your first play through of the original Diablo with The Darkening of Tristram tribute event. Venture through a reimagined version of the original cathedral in Diablo III and keep an eye out for some familiar items.
Heroes of the Storm:
The battle for the High Heavens continues, and a new Diablo-themed portrait is up for grabs! Can you emerge victorious on this hectic new brawl map?
In this Tavern Brawl, a hooded stranger awaits, holding a grim deck in his hands. Will you unravel the secrets surrounding this dark wanderer?
Bring the battle for Sanctuary into the fight for the future with in-game sprays representing your favorite Diablo III classes—along with a new player icon modeled after the Lord of Terror!
Put the Lord of Terror to work for you with a Diablo-themed worker portrait.
World of Warcraft:
Strange things are afoot in the world of Azeroth as denizens of Sanctuary cross over into an unfamiliar world.
All events and items will only be available for a limited time, so be sure to take advantage of them while you can.
Blizzard promises more details soon.