A Forgotten Beast wandered into the caverns of Wirejade. A towering feathered serpent with a trunk and a bloated body, called Radavi the Jackal of Twilight. Able to spray deadly dust. Like many times before, I sent out the military to counter it, expecting at most a few dead soldiers.It sat in the middle of an underground lake, so I decided to provoke it with marksdwarves and make it walk straight into the middle of my troops. It attacked them, just as I expected, and turned towards the rest of the soldiers. Then I noticed the marksdwarves are already dead, despite being hit only with the dust. Checking the health of some animals which were unlucky enough to get caught up in the battle revealed the cause."Deadly" was a major understatement. The dust literally caused the entire body to rupture. Death from blood loss followed within seconds.I evacuated the warriors, and fortunately the beast walked back into the lake. I was already digging out a chunk of the ceiling to drop on its head... I'm not sure what happened then. I think a passing hunter started shooting at it, making it crawl out of the water, and was killed. Afterwards the beast kept moving from dwarf to dwarf, leaving a trail of blood and destruction. About 40 dwarves, including a large portion of the military, died. Damn thing was fast, too - ordering everybody to go back into the fortress proper did little.One of the dwarves who didn't make it was my captain of the guard, Sakzul Riddlegirder the Clean Call, slayer of seven Forgotten Beasts, two of which she literally bisected. Adamantine chain mail, artifact helm and shield, ☼adamantine short sword☼ forged by the duke himself - nothing helped her in any way. The beast slammed her into the wall with its dust... she got up, walked a few steps and promptly collapsed next to a torn apart hyena cub. I didn't mention this infernal serpent is exceptionally good at ripping out limbs. It got hit a few times, though - it's middle spine is broken. Not that it helps much. Other injuries are probably caused by its own dust throwing it into walls.At this point, I decided to seal off the caverns, abandoning whoever was left there to their doom. There are still some survivors, picking wild plump helmets. After that, I did the last thing I hope will get me rid of that abomination.I breached the hollow adamantine spire.This had the downside of having whoever was far below the fortress, in the magma forges level, mercilessly slaughtered in a number of gruesome ways. But hey, the beast would get them sooner or later, right? I ordered them to forge some armament for themselves so they would at least die armed and fighting, and organized them into squads. One received the name "The Evisceration of Smiths". It's more or less an accurate description of what's happening now.Anyway, that brings us where we are now. The demons are assaulting the forges, and dwarves are getting roasted alive and kicked across the room. Smoke, blood, corpses and various metal garbage is everywhere. The beast is slowly destroying the base of my old pumpstack I used to dry an underground pond. Everything below z-level -11 is dead, dying, or will be dead. All that stands between Wirejade and its doom is an artifact bituminous coal hatch cover and some nickel bridges.There are three demons futilely trying to kill a cave blob. One of the others got named "Hatedemons".Current death count: About 100 and increasing, 339 dwarves alive.It isn't over yet.