In searching for a good map (never done good aligned) with flux and no aquifer, I found a Freezing embark square that was Mirthful. I figured, what the hey, let's give it a go. I loaded up with mostly food, booze and wood and headed out. It turns out there's a 15x25 or so area that isn't Freezing, and does grow trees, though the rest of the area appeared featureless.
When I got to digging, I found that the first four layers were sand. I cleared a space to move inside, then proceeded downwards. The next layers were all dolomite and iron ores -- nice! I wanted to save the flux and ore (and not use my miners yet on that level), so I dug a bit deeper to try to find common stone. On level 10, I found granite. Good enough, and I started hollowing out a small area to be able to make doors and cabinets, and to get my stonecrafter going since I knew I'd need whatever the trade caravan brought.
Bang, I got the cavern opened message. Didn't mean to do it so early, but I knew I'd want it ASAP for wood and water to get my farms going, so I thought it a stroke of good luck. I walled it off for now just to be on the safe thing.
Here's the thing though. I started looking through what was exposed. The portions I could see made it look like half an egg at first -- narrower where I had broken out, then expanding from pretty much the point I broke in, to the point where it'd consume my central stairs in a few levels. But as I went down, it stopped expanding, and pretty much just went down, and down, and down. A vaguely circular cavern, no floors to be seen, with a clear line of sight going down until it finally passed out of view somewhere in the level 40s.
Odd. Not really what I was hoping for since I needed trees, but fortunately cracking the cavern brought on some saplings. Due to the pressing need for drink and no immediate method to get water, due to the lack of water, I set my herbalist (and a fortunate herbalist migrant) to start gathering the plants that started to spring up on the sand levels, and started mining out vast stretches of sand to encourage native life to grow.
Once winter hit, I was feeling more comfortable, so I thought it was time to deal with this cavern. Being still a relatively new player, I wasn't sure how to chuck someone in the pit, so I put a puppy in a cage built on a floor extending out into the cavern to see if that would work. I tried to destroy the floor several times but the dwarf responding kept trying to get on the other side. Argh.
Finally I tried just digging a channel to release the constructed floor (about 4 tiles). The responding legendary miner, and also my expedition leader, ran out onto the floor and channeled out so fast that I wasn't able to stop the moron. Fine. Evolution at work, moron. Enjoy your adventure.
As soon as this happened, the game froze up for several minutes. When it worked everything out, there was quite a bit of dust and the miner, of course, was dead. The puppy lived through the fall, it seems, though he's immersed in deep water.
On floor 103.
What the hell - a 93 z-level cavern, straight down? Right in the middle of the map, so I wonder if that means there are no other caverns. You want me to die, don't you?! And no path down. The only floor, other than a few scant ramps on some of the levels, is down at the very bottom, and it's pretty small; most of it's water.
In any case, this is my only known source of water. I wonder, can a well go down that far? Would it be usable? As soon as a dwarf gets hurt, I'm going to need water in an awful hurry. Looking around, there seems to be a very small area that has some tower caps, but not nearly as much as I'd hoped for. Ugh.
My fortress is currently bin-free except for what I've gotten my cloth and leather in, and all barrels are consigned to booze production. And, of course, I got about 25 useless migrants. I don't have nearly enough wood to even provide them beds. Fortunately, despite the lack of containers, the fortress is managing; I have plenty of haulers since I have no farms and little production to speak of, other than my steel industry, which is going nicely. Due to ineptness on the part of my hunter dwarf's shooting ability ('skilled' my ass, when you can't kill one thing with 25 shots), I've consigned my military to try to chase down musk oxen, with very limited success. They don't seem to be fast enough, but have cornered one or two on the edges of the map. Fortunately, my giant mock-farms seem to be providing my plant needs well until I can manage to get pumps going; I've never done a pump stack or any powered machinery, so it'll be interesting to learn. I'd better learn quick as I'm already teetering on the edge here, and I'm concerned as to what's going to happen when that body starts to rot. No chance of retrieval anytime soon.