In addition, the Card Carousel on the Hearthstone website is now showing 5 new cards: , , , and . The characters from each of these cards can be found in Черная гора, teasing the upcoming adventure announcement!
In checking the URLs for these new images they're using a directory named "hots". Could that be the acronym for the new adventure? After the Blackrock Mountain data references we found, it seems like they already have a name ready. And would they really use the "HotS" acronym again after Heart of the Swarm (SC2) and Heroes of the Storm? It seems more likely it was a web developer reusing an old directory accidentally (or intentionally to tease us), but at this point who knows.
More Adventure Teasing
Blizzard has sent out a tweet teasing that "Adventure Awaits!" Aside from mentioning adventures specifically the image is set in Lakeshire, a town in the Красногорье near Черная гора. The text "It's dangerous to go alone!" (a phrase commonly quoted from the first Legend of Zelda game) seems to tease that this could even be a co-op adventure, an idea some have speculated about!
Update: Blizzard has responded to questions of co-op and said that there are no plans for co-op. Sad face.