Microbe Stage GDD


Nice job again!

I personally liked this idea:

“Another solution is to have reproductase transfer the compounds over. In essence, this would involve using reproductase as a label for stored compounds needed to produce offspring. Compounds could be converted to reproductase, and eventually released on death and digestion. This does raise further questions though. If organelles have a set makeup, does an organelle-heavy cell need more reproductase to divide? If more organelles are added as a mutation, where do the required stores for them come from if not thin air?”

In nature, bigger cells take longer to divide and move slower. Having reproductase be the amount of compounds necessary for a cell to split in two gives it an actual scientific meaning rather than simply it being a magical molecule that no-one can understand how it works (add reddit and the old forums are prime examples of this fact).

As for your second question, the organelles you add in the editor could already be factored into reproducase’s cost. By this, I mean that you already have a set amount of mutation points in the editor; assuming the player will always use as much of it as they can, we can multiply 100 by the average amount of compounds an organelle requires. Sometimes the player will put in compounds above this average, sometimes below, but if the player goes in the editor often enough the required stores will balance out—sometimes they will dissapear into thin air, other times they will come out of thin air. Does this make sense?


So the game world as a whole ignores the exact mechanics of how compounds would be transferred between generations? I assume that cells in the player’s field of view (which are simulated fully) wouldn’t feed back into the system in the same way then.

I hadn’t considered using assumptions of how a cell would mutate next generation to calculate an average requirement for reproductase. That sounds like it would work until you realise that Mutation Points don’t just cover adding organelles - they can also be used for upgrading organelles, removing organelles or changing behaviour. None of those actions leave extra organelles to represent the locked up compounds, so there’d still be a compound deficit.

It might still be possible to calculate an average taking these things into account. We’d just have to accept that, for the player’s patch at least, compounds involved in reproduction would eventually deviate wildly from initial values.


Yes, I guess that is true. If the parent has a mass of X and then has an offspring and afterwards both the parent and offspring have a mass of X/2 then the total amount of compounds in the species has not changed. We’re not keeping track of any individuals or anything like that, just the blueprint/genetics of the species and the amount of compounds they are holding in total.

I think the plan when it comes to relating the swimming around with the CPA model is that the swimming around will have no effect on the underlying CPA (if you kill 10 out of 1,000,000 members of a species in your patch that is closer to 0 than anything) however what you experience as you swim around is slaved to the CPA. So if the CPA says your biggest predator is species Y and they outnumber you 50 to 1 then as you swim around you will see 50 of species Y for every one of your own species you meet.

The idea behind this is that when you mutate your creature in the editor you will have to optimise for two things, 1) While swimming around what organelles do I want and 2) in the CPA how can I help my species the most. If the swimming around is slaved to the CPA tightly enough, and the CPA models the swimming around well enough then these two problems should be the same. Ie if you add a flagella and that makes you better able to flee your predators then also your species does better in the CPA for the same reason.

However this is a super complex problem so we’re going to have to wait for some programmers who want to work on it and then let them build what they can and then accept that. I don’t want to get too pie in the sky about it, you could easily do a PhD on this problem (many people do, modelling microbial interactions, for example).


There’s a simple solution to all the problems with reproductase: remove reproductase entirely.

I’m pretty sure that’s already the path we decided on – now that we’ve figured out how to model the-stuff-a-cell-is-made-of (with ‘locked’ compound pools), we no longer need a magical compound to represent the-stuff-we-need-to-make-a-new-cell, because those are one and the same. If an average, healthy cell has a certain amount of each compound, then two of them would have twice as much. Therefore, for a cell to be able to split into two average, healthy cells, it must have twice as much, and then a bit extra to cover the energy needed to reproduce. Note my wording – cancer cells, for example, generally reproduce too early.

How strict we should be about having double of everything is another question entirely (for example, if we have a glut of food protein, can we split earlier even if we don’t have large enough glycogen reserves?), but it provides interesting tradeoffs for gameplay.

The other question, of what we do with changing cell mass through evolution, is simple: The population still has the same amount of each compound, so if each organism is bigger, there are now fewer of them.

I’ll fork off a discussion before this gets even further off-track.


Since I’m about to get tied up in other things again, I’ve added a list of things that need changing to the start of the GDD. Things like replacing reproductase, changing the way external organelles are placed, etc.


That’s now done, so once again everything but the Simulation Specifics section should be fully up to date.

I replaced the internal/external organelle system to one with three classes: internal, external and periphery. Internal and external organelles are placed in the same way (as hex arrangements, no more fiddling around with edges), but external organelles can have their orientation changed in the Appearance tab. Peripheral organelles were discussed here, and cover an entire cell with a shader coating. There are currently only three peripheral organelle types - cilia, lamellipodia and cell walls.

Reproductase is now gone everywhere but the Simulation Specifics section (which I’m yet to update). Hurrah! Instead, compounds are now converted to a locked-up mode, determined by how many organelles a cell has. These locked-up compounds can’t be accessed by any means except when a cell dies, when they’re distributed amongst floating organelles (which already contain the locked-up compounds used in the previous generation to produce them.


Since I’m unlikely to have much time for extensive GDD updating for a while, I’ll to strive to leave it in a state where other people can happily edit it without making a mess. That means adding links between relevant sections (so that when something is changed in one place, other locations where it’s mentioned can be easily found and adjusted accordingly), which I’ll try to get done within the next week.


Given that we’ve finally made some inroads into overhauling the reproduction system and health/combat system, I think we should probably update the GDD to reflect everything that’s been decided on since the last revision. By the time we get to post-0.3.2 outreach, it needs to be as up to date as possible. That includes the simulation page if anyone’s willing to write it. I’ll try and fit in the new game mechanics, as well as updating everywhere else in the GDD they appear.

Given people have still had different assumptions about mechanics, I’d like to ask everyone who considers themselves a contributor to microbe stage discussions to read it. All of it, if you can. Take your time of course, but it would really really help to get everybody on the same page, even if that page is subject to change.

Ignore the parts that are out of date after recent discussion (health, reproduction, the new CPA lists), but otherwise if there’s something drastically different to what you thought was planned, SPEAK NOW (or whenever you finish reading). This is meant to be a self-coherent concept, though still subject to change. If somebody starts a discussion on a topic that doesn’t fit what’s decided upon for the GDD, and they don’t explain what else should be changed to make it fit, I retain the right to be slightly annoyed.


There are a couple things I could point out, but they’ve all been discussed and there hasn’t been any clear consensus on them (such as pilli). I think the GDD at the moment is very good at showing what is planned, but I don’t expect that it should be a final and perfect copy. The final details should be rediscussed when we will be implementing a particular feature—we might run into some problems while actually coding it or it might turn out to detract from experience.

I vote @moopli or @tjwhale for writing the simulations page.


I’ve got quite limited Thrive time at the moment so I’m going to spend it working on the prototypes rather than writing up stuff.

Another issue is that the CPA system might change quite radically when it gets built. We need to play around with it and see what works and what doesn’t to get it to feel right. After that I think it’s worth writing some nice wiki pages so people who are playing can understand it. However before that process has happened I’m not sure it’s worth it. Or at least anyone else is very welcome to write as much as they like.


I had a suggestion for relatively minor changes based on some research I’ve done in the past 24 hours. Just some name changes to make certain game elements more representative of real life.

  1. Agent secretors could/should be called extrusomes. The way @TheCreator described the agent secretors to me is a sphere that buds off smaller spheres filled with agents the player wishes to secrete. In real life, extrusomes are membrane-bound structures that discharge their contents outside the cell. Some notable examples are mucocysts (mucus secretors basically, which are in the GDD) and nematocysts (think tiny venomous harpoon guns. Could be a way to introduce the pilus to the player?).

  2. Rename vacuoles to vesicles. Vesicles is more broad and allows for some specialization early on. Evolve (upgrade) certain vesicles into lysosomes to digest other microbes, secretory vesicles to help with waste removal, transport vesicles to help with protein synthesis, etc etc.

  3. Change “Mitochondria” to “Mitochondrion” in the editor, as mitochondrion is the singular of mitochondria.

I was also curious about how likely it’d be for entirely new game mechanics to be added at a later time.


This is all just preliminary. We can change and chop bits just as much as before, but my intention is to give everyone a clear sense of exactly what the starting point of those changes is. And it won’t hurt to have a comprehensive (if ever-changing) concept when selling ourselves to prospective new developers.


Sure, we can fiddle around with the semantics. Extrusomes could work as long as the player knows what they are (most people know what chloroplasts are for instance, but the more obscure organelles might need explaining). Revamping vacuoles (as vesicles) is a possibility, but from your description that would introduce some new mechanics which we’ll have to review before adding. And yeah, it should definitely be mitochondrion in the editor.


For the extrusome: That’s why we have tooltips!

For the vacuole(vesicle?): Yeah this conversation would be more relevant when the game gets to a point where players can actually upgrade their organelles.

Mitochondrion: Sweet!


I looked through the GDD again and noticed there was a suicide option? Is that still planned?

I have an idea for an alternative if you guys are interested. Most microorganisms, when conditions are unfavorable, have the ability to go into suspended animation as cysts.

In game, instead of committing suicide when your ATP levels drop, the player could be given the option to go into suspended animation until the compound concentration around the cell is enough to “start up” their cell again.


Would the player really want to wait around doing nothing waiting for their cells to gain enough compounds?


Yes, a suicide option is still planned. @stealthstylel is correct - while the player could be given the option of waiting for more compounds, if their metabolism has collapsed it’s likely due to a badly built cell or inhospitable environment.


Well I know some players will want to become immobile microbes that are subject to the whims of the current. But you make a good point.


@NickTheNick and I are working on renovating the GDD (http://thrivegame.wikidot.com/microbe-stage-gdd).

The first step is to make everything more concise and to the point, which we’re achieving with bullet points instead of paragraphs. The second is updating all the information with recent changes, a lot harder as it involved trawling through as much discussion as we can find and finding the latest consensus (see: https://github.com/Revolutionary-Games/Thrive-Organization/issues/15).

Others are free to help.


i could start a thread with some ideas i had for the beginning of the multicellular stage and how to get there from the microbe stage if that helps.


Fun fact, this page was reduced by ~10,000 words. If you have access to history you can see what it looked like before and after. At the moment it’s a little bare because all the information from the remaining 4000 words is being ported over to other pages. If at the end of that we find that the Microbe Gameplay page is unnecessary as a page we’ll delete it.

@crodnu : Yeah if you want go for it. We can start documenting the concept for multicellular because we’ve discussed it a lot but I don’t think we’ve put it all in a central place yet.