Blizzard teases Hearthstone announcement at BlizzCon

Select Hearthstone fansites and general gaming outlets have received curious mail from Blizzard Entertainment over the course of the last week. BlizzPro, Polygon, TouchArcade, and Hearthstone streamer Noxious have each shared a postcard which presents a blueprint of an in-game gadget and the following text: Making plans for BlizzCon -- I hope you like my invention!

These postcards, combined with recent teasers on the Hearthstone website and November's goblin-themed card back, it seems likely BlizzCon will present an expansion themed around the mechanical side of the Warcraft universe and the long-standing goblin/gnome engineering rivalry. Some Hearthstone fans have even been attempting to read between the lines on Blizzard's on-site teasers, speculating on the addition of new game modes, new creature types, and possible new hero abilities. Given BlizzCon begins in less than 24 hours, it might be best to wait and see.