The Obsidian Crypt- one-shot adventure

Once every 100 years, when the stars are aligned and the tides are low, the doors of the Obsidian Crypt open. Those that choose to brave the traps and the danger have 5 days to enter and leave before the doors shut for another century, all for a chance of tasting the infamous hoard of the Dragon buried in this tomb.

The Obsidian Crypt is an adventure best suited to a party of levels 2-4, and would be compatible with any pre-existing campaign as a memorable quest.