I managed to gen a map that I like and dug all the way down to the Cavern layer, which using tweaked parameters was the sort of shape I'm after.
I started to set up an entrance when a resident She-Troll took notice of my mason and chased her all the way back up the main shaft to the surface.
I quickly assigned a meeting area around the entrance and deconstructed my wagon so my small army of wardogs would come to the rescue, they arrived just as the Troll was starting to beat on the mason but she didn't get too badly injured. The first two dogs to arrive attacked the troll, causing little damage but scaring it enough to make it run back down into the cavern with them both in hot pursuit - when they reached the cavern floor a Giant Toad turned up and immediately caught the attention of one of the dogs who broke off to duel the amphibious monster.
I reassigned the meeting area to the entrance at the cavern level so the rest of the dogs would reach the action.
The toad and the other dog fought each other somewhat innefectively for a long time.
Meanwhile the rest of the dogs had joined in on the troll and the rest of my dwarves had congregated at the cavern just as the dogs chased the troll into the meeting area, the dwarves scattered in panic - what ensued was the most hilarious Benny-Hill/Scooby Doo chase scene you can imagine. The dogs chased the troll all over the place, sometimes into parts of the cavern that hadn't been uncovered, so I had no idea what was going on in there until moments later when they would reappear - the dwarves fled from the troll (even though the troll was fleeing from everything else) to all corners of the cavern, conveniently uncovering new areas while doing so. Eventually the dogs bought the troll down so it was unconcious and proceeded to gnaw on it - they're still doing this now as I type and I assume they won't leave the troll til it dies - the rest of the dwarves eventually migrated back to the meeting area just as the duelling toad and dog arrived in the same spot, at that moment the toad grabbed the dog by the hind leg and shook it to death, then seeing it was surrounded by dwarves it bolted for the surface. Meanwhile my fisherman who was on the surface doing his job, and completely oblivious to all this tomfoolery, was utterly shocked when a giant toad came crashing out of the entrance and threw itself into the pond, in a second the wounded and angry beast grabbed the poor fisherman by his lower body and shook him to death just like the dog.
In my head the Benny Hill music was playing the whole time
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