Hidden Fun Staff
The very first time I found Hidden Fun Staff (HFS), I ended up digging into the very bottom of the pit. You know what came out after me? A Demon Lord. Not Toads, not Tentacle Rape (that came later though), nor a few Spirits of Fire. Just a single Demon Lord. He then ascended my giant elaborate ramp staircase, and despite my best efforts, proceeded to open up a can of whoop ass on my entire fort. In the very first moments of battle, he struck down 5 dwarves including my leader. He then proceeded to go on a rampage throughout the warehouse/stockpile district of the fort, setting people on fire, and in total killing over 40 dwarves.
But in the end we killed him. A single Hobunk Miner struck the beast in the head with a pick, and knocked it unconscious, where then almost 20 dwarves swarmed in and beat the fucker to death.
We got some good engravings out of it before... OH MY GOD TENTACLE MONSTERS! WHAT? WHY? Which is a funny story in it's own, as I sent a unskilled Adventurer into the fort to check it out later... and immediately ran into the one that killed so many it got it's own name. What happened? I panicked and threw a bolt at it and lobotomized it. Boom. Headshot.