A massive Dragon Graveyard Kingdom ...

A massive Dragon Graveyard Kingdom built around the corpse of an ancient dragon. The main entrance is a giant dragon skull with glowing eyes and a lava-lit mouth gate. Huge ribs arch over the city like a bone cathedral, with the spine stretching across broken towers and bridges. Inside are ruined houses, dark castle walls, cracked roads, market ruins, storage halls, shrines, lava canals, hanging chains, banners, watchtowers, and a central dragon egg altar. The whole base feels like a dead dragon became a kingdom.