The first and most evil forgotten beast that I have encountered was Midil, a fire-breathing, massive one-eyed cardinal (= bird...). My first successful fortress, and my first breach into the cave was followed by critical errors and underestimating the monsters...
A part from my old (034. version) fortress Zasrimad's, "Crystaltactics'", log:
"- I have been called to the newly found cave. Miners have found blowdarts, shields and other equipments made from wood from the cave - there also seemed to be lot of corpses around, humanoids that look like ants. Small pack of scaled monsters with large claws and horns has been seen on the slopes of underground cave - miners call them "crundles".
- 1st Malachite, Mid-Summer. The 56th level has been secured and woodworkers have been sent in. Up on the surface new bird creatures have been spotted: white stork men, long legged humanoids with the head and wings of a stork. Hopefully not as annoying as those kea-humanoids.
- 21st Limestone, Early Autumn. Large sections of cavern has been secured and felling of trees is almost done. There should be enough space for trees to grow but future shows how much more cavern needs to be captured.
- 24th Limestone. Digging deeper from 56. level started. So far nothing but worthless gems. We'll try to find bituminous coal, but miners said it's usually found in sedimentary stone layers where hematite is found. That's why it was suggested that we start test mining from 6. to 8. level nearer the surface.
- 26th Limestone. Echoes of Forgotten Beast Midil were heard in the deepest cave of 56th level: a winged, one-eyed beast that breathes fire announced its arrival. This is bad because it can fly over the cliff.
- More monsters sighted in the cave: long tailed creatures called rutherers. Luckily path to that part of the cave has been secured by removing ramps.
- 4th Sandstone. Flying monster hasn't been seen in the area for a week so bravest woodcutters have entered the cave in order to collect all trees: steel industry needs more coal. Many haulers have followed their lead.
- On 9th Sandstone Midil The Forgotten Beast appeared suddenly and attacked woodcutters and wood haulers; a massacre!
A huge section of the cavern was in flames as the beast hurled balls of fire one after another. Marksdwarf Kogansárek attacked the beast, hitting it once to right lower leg. War dog that was guarding the entrance burned to death, as did soldier Leklokum and marksdwarves Rakaslór and Zasmómgoz. Smoke filled the tunnel and cave when we escaped; guards Shemsedil and Sĺkzulfesh, marksdwarf Kogansárek, mason Zimkonos and miner Dallithrith were missing after doors were locked. It wont stop the beast but mason blocked the entrance to the inner fortress in time.
One war dog charged the beast after all others fled, inflicting several minor injuries before burning to a crisp.
- 19th Sandstone - four marksdwarf squads and one infantry squad has been sent to deal with the wounded beast. Marksdwarves charged the beast, firing it with crossbows and also engaging into melee fight after the infantry squad. A strike to beast's lungs spilled boiling blood all over the beast, but also over nearby dwarves. Marksdwarves Atírnikuz and Lasgantobul burned to death. Bimegdoth, militia captain of the Mansions of Light, perished to his wounds. Other dwarves received horrible injuries while fighting the beast - fire burned the head of Rakustkesh, the militia captain of the 5th marksdwarf squad.
When day turned to new the beast was dead; finishing blow was given by the famous marksdwarf Ňdadónul Zocukoddom Deler. Bodies of five missing dwarves were never found, only a few tools they had dropped while escaping. Their tombs will stay empty so memorials were build for them."
It's also featured in this animation my bro made, starting from 5 mins:
https://www.youtube.com/watch?v=is1wSwdaM2w
I only had one miracle when 