First of all, this is a longer term idea, and might require mildly unrelated features to be made.
If nothing else, it's a potential modding content.
Also, I haven't played Fortress mode a lot, so please forgive me any mistakes I am inevitably going to make here.
Automatons - otherwise known as robots (and other similar terms) -
before you start flaming me about adding technology to our lovely Dorf Fort, let me explain.
Those automatons are more related to magic than actual technology - they are only "skeletons" out of metal, cogs, levers, and clockwork-related stuff, but it's magic that makes them move. So bear me with me and enjoy this slightly controversial suggestion.In essence,
automatons are creatures that can be crafted - or found underground - by your lovely Urist DaVinci dwarves out of any kind of metal (well, that's the plan, but generally speaking you don't want to use stuff like gold or silver, but more like bronze and brass - but it's your call).
There are a few things that you need in order to be able to construct those machines:Auxillarite - a sub-suggestion - when a creature, be it dwarf, dragon, or carp, dies, its soul is released, and will "flee" to the other world - (some creatures could capture or even entirely eat those souls, for some Fun effects).
Auxillarite is a magical gem that can capture souls within - with yet-undescribed mechanics, souls of still alive creatures can also be put within auxillarite crystals, albeit that's risky,
since once captured in auxillarite, souls can't be put back into bodies (they can be transformed from a crystal to a crystal, though).
Auxillarite crystals come in various sizes - tiny, small, medium, large and huge - and they determine how powerful of a soul can be stored within them. (
Soul's power is determined by the creature's soul attributes and also size of the creature to an extent).
Trying to capture a soul that's more powerful than a crystal one is trying to capture it into will cause the auxillarite to break and the soul to escape forever.
Regular (or blue) auxillarite is used as "brain" substitute for automatons - for instance, you can capture a dying noble's soul into a crystal and put it inside an automaton to prolong his life. More details below.
Red auxillarite - a slightly more common variety of auxillarite, which are used to give power to automatons, sort of like "hearts" or even batteries (or cores) by continuously draining off the power of the soul into the machinery. (Think batteries, but soul attributes are used instead of electricity). Souls still have to be captured within in order for them to function. They also come in 5 size varieties.
Mechanical parts - mildly miscellaneous, they include
cogs, gears and springs - you can think of them as "muscles" for automatons.
Creature knowledge - this shouldn't really bother you
unless you are going to be making non-dwarf automatons/making automatons with non-dwarf body parts[/u] (mildly a spoiler). (I am assuming animal training knowledge here, which is probably not a good thing to do - oh well.)
Mechatronics workshop - used to (de)construct Automatons and also used to give (I can't find a more proper word for it) your creatures (not just dwarves) automaton parts (think prosthesis, also, cyborgs ftw).
Once you have all of those, we can proceed to the fun stuff.
Implementing automatons would also require a new interface, due to a slightly complicated nature of making them.
First - with mechanical parts (and some more metal bars), you are able to create creature body parts at the metalsmith's forge - they include all regular and modded bodyparts, ranging from upper and lower bodies to wings, pincers and teeth (why would you want to make those is beyond me, unless, well, read below). You can also forge organs like lungs and the like, but they won't be functional, because, well, what's the point?
Also, weapons and tools are counted as bodyparts for that matter, so Urist Scissorhands is not out of the question. (note that they have to replace hands, so unless you are going to give your automatons multiple hands you leave them with one or even no way to grasp stuff with)
When you have created 2 pairs of limbs, upper and lower bodies and a head (that's the most basic combination - you can go ahead and try out some more crazy combos), you will have to arrange them using the following method:
There are two columns - left and right.
The left column contains bodyparts at your disposal to craft your automatons with.
The left column shows their arrangment.
It kinda works like containers, of sorts, where you can either put some parts "within" other parts (feet within legs, for instance). Well, it's just called connecting them, but whatever. You can't combine them in any way, though. (you can't attach wings to a head, for instance). You can, however, combine dwarf lower body with elephant legs, for instance. You get the idea.
You can have incomplete automatons, but they won't do you much good, if anything. You can leave them and come back later to finish, modify or deconstruct them.
Auxillarite (blue) crystals always go to the head (if there's one) while red auxillarite crystals are only attachable to the upper body (or something that has a similar function).
Once you have your first automaton ready, with limbs, body, two auxillarite crystals with soul(s) within, it will be able to function, move and use stuff. It's worth noting that your dwarves WILL loose their body-related skills (mining etc.) when they are put within an automaton, but soul skills are unaffected.
It is worth noting that automatons do NOT need a soul within a blue auxillarite crystal to function, but they won't gain skills or attributes.
Now, while automatons can be very different among themselves, there are a few features that are persistent between them:
They do not die of old age, they don't need to drink, eat, or sleep (and will not gain bad thoughts from them). They are able to enter strange moods, but only if there's have a humanoid soul in the blue auxillarite crystal. They won't go insane, though.
Automatons' skills and attributes do not rust, and they will be able to raise, only if there's a soul in the blue auxillarite crystal. (It doesn't need to be a dwarf or even a humanoid soul, though, but it's not really worth to have carps running around your fortress). Their bodyparts ARE affected by item qualities and they posses the same statistics as the material they're made of (so a silver hand will pack quite a punch, for example).
Automaton body parts can be decorated if you so desire. They can be decorated with pretty much everything, but they don't count as furniture, in case you're wondering. But if you plan to sell them (which is totally plausible, but the automaton has to be disabled when being sold).
Various automatons can be also found underground, and will come in a HUGE variety of...Varieties. (there could be also a half-random automaton generation). They may OR MAY NOT be disabled, which raises the Fun potential.
Automatons can be given various tools/weapons instead of certain bodyparts (mostly hands, but also arms as a whole, legs, and possibly even tails) and if plausible, they will gain skills from using them. (that means however they won't be able to drop them, but will be able to be removed and replaced at mechatronics workshop.
You can also attach automaton bodyparts to alive creatures (especially useful for those who lost their limbs in battle), and they will function exactly as they would for automatons.
With this system, you have effectively an in-game creature editor, albeit somewhat limited. (but hey, modding could make it that much more expandable) Create robotic armies of flying adamantine hydras (now features 14 heads!), assuming you can pay the bills.
Also, don't forget Adventurer Mode possibilities. (I can't think of any atm, but it would surely also impact that one)
I hope I covered this slightly controversial topic the best I could and I hope that it will come to the game at one point or another, in some way, shape, or form.
(this is also pretty much a direct reference to Heavenly Forge from Might&Magic series)