Lost Cavern Introduced - a Single Lane Teamfight Map

Blizzard has unveiled the next map to be added to the Heroes of the Storm rotation that is a fundamental departure from the current maps. Unlike the others, Lost Cavern will have all action taking place in a single land without map objectives, hearthstones, starting area heals and the like removed to keep the action focused.

Lost Caverns does come with the caveat that it is only available in custom games.

You can read the full preview on the Heroes of the Storm site.