“The Forge of the Night Sky” by Chang Yuan, showing the Ruins of Ossiphagan as described in the third Kickstarter update:

The erupting volcanoes and surging lava fill the air with acrid smoke and choking fumes. The bones of an enormous beast lie sprawled across the obsidian fields, its ribs splayed open as if it had been torn open by some unimaginable predator. The ossified bones have been hollowed out as homes by some intrepid or foolish citizens, and the wind howls through the openings in a mournful whistle like a giant flute. In the wastes beyond, creatures of flame and focused minds trawl the lava and skim its valuable nutrients.

Wallpaper resolutions available here.