With BlizzCon 2014 on the horizon, Blizzard is getting us hyped for a big announcement pertaining to its digital card game, Hearthstone: Heroes of Warcraft. 

Polygon reports that Blizzard has sent them a postcard, hinting towards some kind of project it undoubtedly will announce at BlizzCon 2014 later this week. Blizzard's postcard to Polygon (featured above) had the blueprints for a Harvest Golem, an enemy type seen in World of Warcraft's lower level zones. A note accompanied the postcard, saying "Making plans for BlizzCon -- I Hope you like my invention!"

Other gaming sites have received other postcards that featured different blueprints but with the same note. These other blueprints included a Repair Bot and a Demolisher tank. The strange thing about these blueprints is that they are all previously existing cards in Hearthstone. Perhaps Blizzard intends to add an Engineer-type deck, or maybe there is a Gnome or Goblin-themed expansion in the works?

BlizzCon 2014 will be happening on Nov. 7-8.

There's no friendly Engineering here: