Okay, in one of my previous fortresses i had a bumper-crop of captured gobbies.. my zoo was overflowing, i had like 50 gobbies in cages. I had the execution chamber & was slowly wittling away at their numbers that way, but at some point i decided it would be fun to build, deep within the bowels of the mountain, an isolated gobby habitat. i could dump them in & keep an eye on them, watch their movements & maybe get them to fight eachother, or any other monsters i captured.
I dug out a largish chamber 4 z-levels deep with a small pond in the middle and a few outer rooms for the gobbies to fight over/play in. I even gave them a little gobby temple complete with a statue (up on a ledge so they couldnt reach) and a small amount of coins & baubles for them.
The plan also included the ability to flood the entire chamber (and drain it of course) if i decided to wipe out the bunch of them. Also an upper chamber where my archers could shoot in on them from arrow slits. Additionally i had a set of windows on high side of one side of the room so that the gobbitarium could be viewed from my meeting hall. This turned out to be a problem as the dwarves relaxing in the meeting hall found the sight of uncaged gobbies unnerving so i ended up covering them up.
All entrances were protected by a drawbridge system protected by a ledge so nobody could break out. There were two ways in, a primary entrance 4 spaces wide, for cleaning out the place when it was unoccupied, and a series of a half-dozen 1-space wide hallways lined with cage traps in case i decided to re-capture the gobbies.
The only other way to get in was to be dropped from above. I experimented with a couple different ways to achieve this. Simply setting the holes as pits & ordering the gobbies to be dumped in resulted in disaster when the dwarf got the gobby out of the cage & the now loose gooby wreaked havoc all over my zoo before being shot to death by a guard who happened to be taking a break there. So i had to get more creative with my gobby insertion techniques.
Firstly, i wanted them to be good & injured when i dropped them in. Stunned at least. The Gobbitorium primary room was 4 z-levels deep which killed my test-kittens so i put a platform in there to drop them onto. I ended up with 4 drop-holes. The first dropped only 2 z-levels which i found only stunned the gobbies. The next dropped 3 z-levels which usually injured them a little. The next dropped all 4 z-levels onto the floor with generally resulted in a broken limb of some sort. And the last dropped them 4 z-levels into a pool which stunned the gobbies but rarely injured them. Altho some gobbies did end up drowning.
The problem i had was my insertion technique. Above the main gobbitorium room i had a series of rooms with passages leading into them. Each room was 2 spaces wide & had a ledge at one end to put the cage on, a 2x2 hole which led into gobbitorium, and another ledge at the other end where the bridge would fold up and block the only door. The idea being that you would first pull the lever attached to the cage, releasing the gobby who would then hopefully wander out onto the bridge which would then retract when you pulled its lever. In practice, however, the gobbys usually would just hang out on the ledge for a long time. If you set the bridge lever to repeat eventually he'd get dropped in, but the process could take a whole season. Not acceptable. It also had the additional problem that many times the cage would get dropped in too, leaving it in the gobbitorium where it wasnt easily retrieved.
My next gobby insertion technique didnt fare any better. I dug the bottom of the pond out and dug out a room below the gobbitorium. I put a drawbridge at the bottom of the pond and set up a sistern to flood the bottom room. The idea was to put a bunch of caged gobbies in the bottom room, either release them & then flood, or do it the other way around, open the drawbridge & they would float up to the surface (inside the gobbitorium proper) Then i could close that drawbridge sealing the bottom of the pond and enabling me to drain the lower chamber & retrieve my cages.
No such luck. The gobbies just drowned never leaving the bottom room. Apparently they cannot swim up through where the drawbridge was, even when its open.
So back i went to dropping them from above. Eventually i used an altered version of my first technique, adding a smallish cistern (2x2x2) above each drop-room which would give a gush of water just big enough to shove the gobby off the ledge & into the gobbitorium.
Unfortunately before i could finish the final preparations, the new version of DF came out & i quickly lost interest in that fort.
I am planning on building another gobbitorium though. And thats more or less the purpose of this post. Have any of you attempted to build a gobby habitat within your fortress? were you any more successful than I? What methods for gobby-insertion did you use & what alterations to my systems would you suggest?