Me and @Rathalos recently discussed Multicellular mechanics, and one big takeaway was some discussion on parts. I don’t think Multicellular Parts should be our crux of adding new features to the stage - making sure that specialization and adjacency are engaging and well-balanced will be like 80% of making the Multicellular Stage unique - but they do represent unique opportunities.
Rathalos will likely have their own ideas regarding this parts, but I am proposing some baseline ideas and a general framework for how they can look.
Big Takeaways
Multicellular Parts can represent the “roots” of larger organ system functions.
Placing down a multicellular part can represent a watershed moment in the evolution of multicellular lifeforms, symbolizing transitions towards structures that are conducive to macroscopic life.
Digestive Complex
Serving as the root of a digestive system, such a part will be focused on unlocking extracellular digestion.
The part to be placed is a Digestive Complex.
An agent is shot at other cells. If this agent hits another cell, it is a target for digestion.
If within a certain proximity, the target cell takes damage, and the player absorbs phosphate, ammonia, and glucose.
Must be placed in a cell type that has lysosomes in it.
This represents the roots of structures like internal cavities - as Rathalos pointed out, the stomach really is just a “pouch of external digestion”. It also allows organisms with a cell wall digestion capabilities.
Reproductive Complex
Placement unlocks sexual reproduction, and indicates the beginnings of more dedicated handling of genetic material that is often employed by larger, complex organisms.
Generic discount to MP.
-10% cell count cost.
“Circulatory” Complex
Put in quotation marks because a “circulatory system” isn’t really a thing in tiny multicellular organisms - atleast, as we know it in larger organisms. Rather, circulation in these smaller organisms is often focused on extremely simple transfer of fluids within a cell.
All adjacent cells get boosts to adjacency bonus effect strength, regardless of type.
Placing multiple of this cell type adjacent to each other boosts this effect.
Signalling Complex
This is a sort of stand-in for a “nervous system”, but it is a more neutral term to accommodate the fact that plants don’t really have a nervous system - just complex signalling/enzymatic capabilities.
+30% cell count cost.
All adjacency bonuses boosted by 20%.
Massive ATP cost, likely requiring a highly-specialized cell.
Stage Progress Condition
Having these parts can be tied to win conditions for the stage. For example:
Have a Reproductive Part
Have a Signalling Part
Reach 20(?) Cells.
I haven’t fully fleshed out the idea, but I atleast want to put it out there to generate some discussion on its feasibility, use, etc. More advanced capabilities might be cool with something like the signaling complex, but I’m not fully sure as of now what that could be.
Interesting ideas, but I’m slightly worried for the roadmap as I’d estimate 1-2 weeks development time for each of these new cell archetypes (I suppose this is a fine enough name, though it is more programming inspired than biology).
Not sure I super like the “shoot an agent” part? Would this be “aimed” by the player or automatically fired in the right direction? Would simply the area of effect requirement be enough? I do like the simplicity of that by the way. I was thinking of the digestive enzymes like another agent cloud like mucilage, but that would be a lot more complicated.
I was thinking that the damage caused by this should be quite low, so that it is really only useful against things that are already dead, or completely trapped.
After some back and forth with Hhyyrylainen I realised that IRL specific germ cells aren’t really necessary for sexual reproduction, but they are a big improvement to the process.
I am thinking switching to sexual reproduction via the editor tab would already be available, but have some downsides next to upsides, with the situation improved by having Germ Cells.
I made some suggestions in the other thread for various ways to make internal cavities work. That would also essentially fill this role. (Those were essentially what I had in mind when suggesting a transport system)
There’s also the possibility of splitting this into two things:
A hormone-like system that is a requirement for anyone to advance to the next stage
A nerve-like system that is only relevant for highly motile species
Because we probably also want to start thinking about the difference between plants and animals in the transition to Macroscopic.
I thought about clouds too since that would be most similar to the actual biology involved in external digestion, but I just know it would be pretty difficult for the player to consistently utilize.
My thought with the projectile was it essentially being a focused of the damage and digestion effect. But on second thought, relying fully on area of effect instead of a projectile could encourage some really interesting builds. For example, pulling cilia on that part drawing prey in to be close enough, incentives for cavities so that organisms are stuck, etc.
I see the suggestion related to the placement of “empty cells”, but was there anything about impact on stats? I think there would definitely be a ton of fun soft benefits when it comes to the design of organisms, but how do we tie this to circulation stat in a way that is significant to being trackable as a progress condition? Do we conceptualize another stat proximate g how much circulation a cell gets depending on how many exposed faces there are? The editor design benefits are good by themselves, but I’d find it hard to task the players with this as a progression condition if there isn’t something tracked beyond just count of open cavities.
I actually like this distinction, and it could be a good way of distinguishing between sessile gameplay and active gameplay (atleast at the start) of the macroscopic. The motile nerve system proxy could act a lot like the previous effects of myofibril (though I’d advocate for a different model/name since myofibril is a prettt advanced structure).
Fair point there. There are several different versions of the suggestion there: non-cell parts, cells that fill up the space they’re in with non-cell stuff or “background” cells that have a filled space above them. All three of them could be used to implement something like “mesohyl”, which is the skeleton/internal transportation system of sponges or indeed the fluid-filled body cavity of other animals.
These exactly could have the attributes you mention:
And you didn’t list “Circulatory” Complex as an advancement requirement yourself, which I think makes sense, because simple macroscopic plants/macro-algae and fungi don’t have this kind if thing I believe, instead they’re just thin. (Though complex plants definitely do have cavities!)
So cavities/transport system would be more something for if you want any thickness to your design and/or provide those bonuses.
As progression requirements what you did mention makes more sense:
And perhaps reaching 20 cells could require either a spindly shape, or require cavities to not suffocate yourself? (so a surface area for cells mechanic).
An addition we could have here: Nerve system (or primitive equivalent) if you want to be motile in Macroscopic, otherwise your large body is too uncoordinated to really move.
I would still want to have “muscle” as the thing that actually makes you move, while the “nerve” cells boost things. But for those muscle cells, we can have actomyosin fibres that are not organised into myofibrils. This is what you see in smooth muscle tissue (as opposed to skeletal muscle) and simple animals. That would require a new model though.
March 26th:
Since we’re trying to figure out a roadmap for our Multicellular stage designs, I figured I should write up a first design proposal on how our “muscle cellpart” would actually work. First things to note:
We can’t have flexible multicellular organisms, so we can’t really show organisms moving as they would. But we can give the cell parts mechanical effects that would be produced as if they could flex the organism, in movement, turning, etc. (I am also guessing we cannot make the cells themselves flex, but at least the cell parts themselves should be able to be animated?)
Some of the attributes I suggest depend on other changes to the Stage’s mechanics that may or may not happen.
I have tried to keep required complexity to a minimum, because Thrive can be difficult enough for people to understand already.
In real life for example a worm has both length-wise and lateral muscles to move. I have abstracted that out here, because of the low number of cells and the previous point. But also, that isn’t always the case, for example in C.elegans, which I based a lot of this mechanic on, moving via only longitudinal muscles.
Having said that, here it is:
Cell part - Actomyosin
model: a smaller/thinner/slimmer version of a myofibril. (But potentially multiple in a cross/rounded shape instead of a line).
Requires normal or double membranes. (Perhaps also possible in cellulose/chitin, but at reduced effectiveness)
On the simplest level: boosts both movement speed and turning speed. If not trying to make placement complicated, that’s it. But if we want to add more complexity:
Lining up more of them in the direction of movement adds more speed (beyond just adjacency)
Movement speed is also boosted by any adjacent cells (not just other muscle cells), because those are also “pulled along”.
Having them off-center from the origin is required to increase turning speed in that same direction.
If we make Flagella and Cilia only function when on the “outside” of the organism, the muscle cells do not have that restriction.
Instead of a constant force like flagella, there is an “oscillating” force application, to mimic swimming.
There could be some delay in muscle activation that is counteracted if you have nerve cells. IN any case, I am still thinking of a way for nerve cells to combo with muscles very well.
The objective here is to balance things so that muscles are the logical way to move large Multicellular Stage organisms, and flagella are less effective.
Bonus:
While animal muscles use contractile elements in cells to make the cells contract (and pull on things the cell is connected to), the rigidity of cell walls makes this not as feasible in plants. But plants do have an alternative solution: hydraulics.
Precisely because plants do have that semi-rigid but somewhat elastic cell wall, it allows plants to use turgor pressure: the osmotic value inside the cell draws water in, but this runs up against the compressive force of the cell wall, making the whole rigid and strong. This is how herbaceous plants can stand up at all, and why they flop down when low on water.
But beyond that as seen in some species for leaf movement of various types, and of course some carnivorous plants, this effect can be used for pressure: by increasing the osmotic pressure, plant cells can press harder on their cell walls, pushing outwards (contrasting with muscle pulling). From what I can tell, the max strength you could reach with this isn’t necessarily weaker than with muscles, just slower and less precise. The big benefit is that while changing pressure costs energy, keeping the pressure on does not which is quite unlike muscles!
Now of course IRL plants and fungi don’t make as extensive use of this as animals do with muscles, but that doesn’t mean Thrive with cell walls can’t! Which is why I think it would be nice to also have:
Cell part - Hydraulic Vacuole
This is pretty much the “plant” counterpart to the actomyosin part.
Model: like a vacuole, but more stretched out in a vertical direction.
Requires Chitin or Cellulose membrane.
Functions largely like actomyosin, but with key differences:
The given speeds per organelle are lower.
ATP consumption is much lower.
Time between movement pulses is much longer.
Delays are longer.
Any position-relative effects that actomyosin has are mirrored. For example, you need hydraulic cells on the left to push you to the right instead of muscle cells on the right to pull you to the right.
The intention here is to:
Put realistic constraints on the type of cells muscles work in in real life while still allowing good motility in 4/6 membrane types.
Make cell-wall having species and wall-less species significantly different in the long-run, even in Macroscopic and beyond. For example, macroscopic motile creatures with cell walls would be like fantasy walking plants: slow, but powerful and tireless.