DF2014 Talk:Mass pitting

42.06 Likely has something to do with the new conflict level system. A combination of necromancers, undead siegers, and evil weather husks were pitted with the repeating spikes on, which resulted in escape attempts and fighting. The same set of creatures were pitted again with spike off (until everything has been pitted) and there were no issues. (perhaps this is intentional, as invaders try to make a desperate paniced escape for their life despite being naked? when they notice others are being executed)

-likewise, members of a military squad may sometimes get into random fights with civilians that is neither loyalty cascade, a crime, or defection from the civ. This happens when others in their squad are in conflict elsewhere. 

March31: still getting occasional escapees in 42.06. Has happened with caged goblins and undead from a siege. Not quite sure what happens but suddenly they just get released or all aggressive and start attacking the hauler (it's not the case from before where other friendlies attack them and they still get hauled). This doesn't occur all the time but it's regular enough that i started building the cages to be pitted in my barracks and "pitting" them from a ledge into my training squads who promptly kill them; if they interrupt the hauler then they get killed anyway since they were being dragged from the bottom level of the barrack to the ledge. For some reason, this seems to only affect pitting (i only pit one at a time, so no interruptions from previously pitted creatures). Transferring goblins/undead siegers to a second cage seem to not set off their attacks.

Unfortunately this system won't work for anything but tame animals. The Pit/Pond information won't allow you to select Goblins in a cage, so you just spent a bunch of time for nothing.

Re: 40.x

Hey guys I did some experimentation and it appears that normal enemies (non-flying non-thief) can be prevented from escaping mass pits by having forbidden hatches over the top of the pits. Not sure of the behavior with thieves/flyers as I've yet to catch one.

~ Lasserith

Hatches must be forbidden before pitting, else they can get a finger in and slip out (even though they are below the hatch)Mesmerism (talk) 04:39, 28 October 2014 (UTC)

Attempted !SCIENCE!

Having had Goblins escape in 0.40.24, my dwarves have been conducting experiments with a new batch of mostly Troll prisoners. However, so far all have been suddenly pitted. The setup is almost exactly as in the article: animal stockpile with hatches to ensure every cage is next to a hatch. Hatches forbidden. Floor smoothed, though I have still had escapees with a smoothed floor so I don't know if that changes anything. I tried with multiple pit zones (pitting only enemies next to the zone each time) and with a single pit zone (pitting all at once). Pitting was no problem even when there were trolls running around under the hatches. Orthogonal and diagonal pitting worked equally well. We are therefore perplexed. Possible differences compared to failed attempts (for further enquiry):

- The lower level (z-1) was completely smooth this time

- This pitting was done shortly (about 10-15 days) after an attack failed miserably. Could time spent in cages be a factor? Could fear and stress from seeing decimated comrades be a factor?

- Most of my dwarves have minor discipline experience. However I'm fairly sure the goblin was pitted by a 0 EXP dwarf, and goblins have previously escaped much more readily than trolls.

So it is still unknown what is causing the problem. However it is clear that the recommended layout still works, as long as the unknown factor allowing escapes doesn't come into play. 90.44.54.59 13:27, 8 April 2015 (UTC)

Related to the above, using the posted layout presented no problems with small (<1 creature / hole) pitting jobs. For larger jobs, escapes were observed, even with overhanging hatches (not forbidden) employed. During these incidents, there was no detritus on the hatches. Escapees included beak dogs, trolls, and goblins. The same layout was used to suddenly perform large pitting jobs provided the hatches were, as instructed, forbidden and tightly closed. So it seems to me that, at least, forbidding and tightly closing hatches over mass pitting operations solves the issue nicely.

~ BCM 108.61.228.8 21:51, 12 March 2016 (UTC)

Points to clarify

Greetings. Maybe we can tackle this problem by sorting out and eliminating various possibilities which could be the reason for this new behaviour.

Can someone:

- Confirm when the break out of the caged prisoner happens? For example, does it only happen when they are pitted, but not when they are lead somewhere else? If so, the release from the cage should not be the reason, but the pitting instead.

- Confirm if or if not the sight of previously released prisoners on the lower floor might be the reason for the dwarf in question to panic, and therefore release the prisoner which is currently to be pitted? I read on the forum, that Jacko13 supposed this could be the case (last post in this topic: http://www.bay12forums.com/smf/index.php?topic=141361.30). So the dwarf opens the hatch to drop the current prisoner in, spots a previously released (free) target on the level below, panics and releases his captive instead of pitting it. If this is the case, it should not happen when the pit below is empty, or deep enough.

- Check in some way, if the escape occurs because the pitted enemies grab the floor of the z-level from which they are pitted when they are thrown into the pit through the hatch? If that is the case, enemies which cannot climb should always be pitted suddenly, while enemies with high climbing skills should almost always escape.

~ Beryll (talk) 09:08, 22 April 2015 (UTC)

Some reasons for escaping

In v0.40.24, I discovered two causes for the failed pitting attempts (on troll recruits):

1. Pitting two or more hostile creatures simultaneously through the same hatch. (This is also reported in the forums.)

2. The hatch cover has one or more items on it, e.g. the body parts of escapees.

Solutions:

1. Try pitting one creature at a time through one hole. Invaders usually have names, so you can just look inside the cages (k-Enter) to figure out, who is safe to pit next. Warning: two of my trolls had the same name and profession, so care must be taken. I have not discovered any problems while pitting creatures through separate hatches at the same time.

2. You could mass dump (d-b-d) all the items on the hatches. The hatch cover will also be marked for dumping, but that should not cause any problems, as long as the hatches are not removed. You can always remove the dump from them later with (t-d), or (k-d) if they have been deconstructed.

Info:

I had not marked the hatches forbidden nor kept them tightly closed. The pitted creatures had no nearby walls to grab, and would fall 34 z-levels down to their instant deaths, so none of them could have climbed back up. In an earlier, less deep version of this pit, they did climb, and not even two levels of carved fortifications could stop the trolls! Perhaps smoothed natural wall works better.

I hope these observations are useful. There is still room for more detailed research, like WHY things behave this way (bugs, skilled climbers, etc.), but, for now, I leave that for the more experienced dwarven scientists to figure out.

~MarkDwarf (unregistered)