This zipped file contains an adventure mode save - the forgotten beast Osman the Puzzle of Poisons, a giant quadruped composed of yellow grossular.

As the forgotten beast, you begin in the caverns just to the north of the fortress. Since the dawn of time, Osman has wandered the depths of the world, bringing terror to all manner of creatures. When it found the dwarves, however, the legendary creature demonstrated unrivaled wisdom, and kept its distance. From a hidden vantage point on the fringes of the fortress, the Puzzle of Poisons watched the rise and fall of Weatherwires, waiting for the day when it would reclaim these caverns as its own. Now that the last dwarf has perished, it is time to cleanse your caverns of the taint of the surface world: make your way into the dome through the watery passages to the south, find the goblin interlopers, and slay them all.

For whatever reason, my most recent fortress crashes whenever it ends (either by abandoning or defeat), which renders it normally unexplorable in adventure mode. So, I used dfhack to take control of citizens in the fort, switch to adventure mode, and then save - so curious people can actually explore Weatherwires.

If you haven't yet, check out the forum thread (link below) and see what this fort is all about.