When you read this, don't call me an idiot, please. Even though I was.
One of my fortresses had some very funny, face-palm-worthy moments in it. I was still quite an inexperienced player, and my fort had about fifty dwarves in it. I had caught some goblins in my cage traps, and was attempting to execute them. Two would be my prototypes. One I tried to drown, the other to dwarven atom smash. I did not know how to do either. I also did not know how to take away the goblin's weapons and armour. To drown the goblin I chained him up by a lake, then tried to dig the block next to him, leading into the lake. Of course, my miner became scared and refused to dig it. I couldn't remove him either, and, since I did not know how to use military well either, I couldn't kill it. The other goblin I had put in a room that looked like this:
WTTTW
WTTTW
WOOLW W= Wall, O= nOthing, C= Chain, G= Goblin, T= cage Trap, B= Bridge, L= Lever attached to Bridge.
WOOOW
WOOOW
WOOOW
WCGOW
WOOOW
WOOOW
WOOOW
WOOOW
WWWW
When the lever is pulled, it turns into this:
WTTTW
WTTTW
WOOLW
WOBOW
WOBOW
WOBOW
WCBOW
WOBOW
WOBOW
WOBOW
WOBOW
WWWW
Of course, the person who pulls the lever gets scared and runs away when he sees the goblin too. This was made expecially annoying by the fact that the goblins were in full view of my main workshop area, so all my dwarves were too scared of them to do any work. I figured that I had to do something about this. So I sent part of my military, which, unbeknownst to me, consisted of 1 speardwarf, to attack the one by the lake. Very surprisingly, he killed it. I looked in his inventory. He was armed with a... pickaxe.
He did the job, though. Next, I sent the rest of my military to kill the other one. This did not work so well. The goblin took all six of them out. Two fell intro traps, and the rest were knocked out. Apparently, the goblin did not feel like killing them. So I send my speardwarf over to attack the the goblin. HE KILLS IT. I am very happy with this, until this happens:
The lever had been set on "Pull the lever: repeat for the last couple of years, and nobody could do it. Now, they could! The first good little dwarf comes along, pulls the lever, the bridge comes down and....
crushes two unconcious military dwarves, and my speardwarf.
FACEPALM!
Made even worse by the fact that a siege comes along. All my traps were full from the last siege, and all my military is in the hospital or in cages. Every last dwarf was killed.