Prokaryote Gameplay


Just to throw in my thoughts on the discussions recently in Slack on prokaryote gameplay.

Game Start

I think the best start is to start as a single hex of cytoplasm. The only thing you can choose is your initial mode of respiration (i.e. what molecule you consume to produce energy). For many cells it’ll be fermentation, which is using glucose to produce energy (using oxygen to break down glucose, aka aerobic respiration, hasn’t evolved yet). For some cells though it’ll be using iron, and for others maybe some other chemical.

That is all you can choose. Then you spawn as the single hex and you swim around (albeit slowly since you have no movement organelles). I think it’s better not to start in the editor, but to save that to “reveal” to the player later, when they reproduce for the first time. I think it makes more sense to introduce them to the gameplay first, then to the fact that they can customize their abilities for the gameplay.

This basically leaves the player with a totally blank book to write the story of their species’ evolution, instead of starting with some of it already filled up. I was thinking we could even start the game with a cutscene of floating DNA merging into a floating bubble of membrane (called protocells or mycelles) to form the first cell, which the player then takes over and plays as.

Prokaryote Organelles

There was also a question about how to handle the transition of prokaryotes, who use proteins to do photosynthesis and aerobic respiration, to eukaryotes, who use chloroplasts and mitochondria, also called endosymbiont organelles. There were two approaches that were brought up (please point out if I’m missing any) on how to implement the energy producing organelles (Bioenergetic organelles? Energy Organelles?).

A) Proteins auto upgrade into endosymbiont organelles: If you are a prokaryote, and you evolve into a eukaryote, then all of your proteins automatically evolve into their eukaryotic counterparts (like aerobic respiration proteins into mitochondria). If you ever evolve back into a prokaryote, the organelles also evolve back.

B) Proteins and endosymbiont organelles can exist simultaneously, but endosymbionts are more efficient: From Andross’ post: “I like the idea of protein organelles as well. In fact, I think that these should still be options for Eukaryotes. My idea is that any cell can have these proteins, they are less expensive (mutation point wise), less efficient, but don’t require a nucleus to function. Then, the organelles that we currently have in the game would be “upgrades” in the sense that they are more expensive, more efficient, but require a nucleus to orchestrate their functions.”

I personally think option A is better, because it allows for a quick and easy transition between them and is overall pretty simple. What do you guys think?


Naturally since I proposed idea B I prefer it. One big argument is that I don’t really like the idea of removing options from the player that they previously had.

I like the idea of starting as a blank slate but I’m worried the start of the game would just be painfully boring if you’re forced to play a single hex.


I disagree with option A, mainly because then there’s no point to endosymbiosis and unlocking the mitochondria if you already have aerobic proteins. Although, depending on when the transition from pro- to eukaryote occurs, aerobic respiration might not evolve until way later. Still, you’ll immediately have your proteins as endosymbiotic organelles which eliminates the need for doing endosymbiosis and unlocking them yourself. I guess it depends on how much endosymbiosis we want the player to be doing and whether that’s good gameplay


@NickTheNick I agree with that start, sounds great.

@andross I think we can test whether being a single hex is boring relatively easily. You can still swim around and avoid other cells and eat nutrients. Moreover you would only be a single hex for one session and in your first editor session you could add more interesting organelles (for example pilus) which would open things up nicely.

I also think it would work well as a tutorial, if the player can only move they can learn how to do that before unlocking new abilities and learning how to use them in a gradual way.


It’s worth at least play testing I suppose. I just don’t want to bore people right away and turn them off from the game. Although the feeling of progress knowing you came from a single hex to apex predatory cell might be worth it.


100% agree the beginning should not be boring!

One option I suppose is to make the compound cost of reproduction proportional to cell size (which it may be already I’m not sure). That way as a single hex you can get into the editor really quickly and grow quite rapidly to a larger cell. Then the game slows down once you are bigger for a meatier experience.

I think this is how rpg’s usually do leveling mechanics, you get levels and upgrades easily at the start and then they spread them out so you have to work harder for the higher level ones.


Currently you get to the editor once all of your organelles have split (received enough compounds to create a copy), except cytoplasm (I’m quite sure about this but not 100%) so with just cytoplasm you could actually just immediately enter the editor.

I like this idea. Gives some fast progress right at the start.


If I recall correctly we can even define what it costs for a organelle to grow already.


Which means when we change the compounds we will have to update those costs anyway.


I read through this thread again and have been thinking about it. There’s lots of good ideas from everyone. Here is a possible way the early game could work, what do you think? Try to imagine you are a new player who has never played the game before and you don’t know anything about microbiology, so you’re a complete beginner.

As above you start as a single hex of cytoplasm, you’re the only living thing on the planet, the first life form. You start in the hydrothermal vent biome. The game tells you to use wasd + mouse to move and then gives you the goal of getting enough ammonia and phosphates to reproduce, glucose is abundant. You swim around for 20-30 seconds and then the editor unlocks and you go into it.

In the editor everything is greyed out apart from Pilus, Flagella and Chemoplast. You have just enough mutation points to add one of these. You are told by the tutorial to choose one to add.

Then you go back to swimming around. The original species still exists, as well as another new one (for example if you chose a flagella there can be another species which has a Pilus) and the population system is introduced. You swim around and gather compounds to reproduce. If your new species dies out you are allowed to go back to being the original, single hex of cytoplasm species.

Next time you enter the editor all the organelles available to prokaryotes are unlocked (all the proteins etc). This is easy to achieve as you are small and compounds are still relatively abundant.

The game then proceeds with swimming + editing as usual. Over time the abundance of free floating compounds decreases and you have to rely more on either predation or making your own sugar. Moreover as you get bigger and more complex it takes more ammonia + phosphates to reproduce. We need to nail down at some point exactly how species split. Does it split the populations too etc? Also when your species is wiped out who can you then play as? Can you be any other species (maybe this could be an easy mode) or can you only be direct ancestors of yours, if they still exist?

We could then have it earthlike that only you, the player, can add a nucleus. After you have done this all eukaryotes are then descended from your original eukaryotic cell, with the same species splitting that happened for prokaryotes from a single ancestor. The rest of the organelles become unlocked (maybe with the constraint that you need to engulf some prokaryotes to unlock chloroplasts etc) and you can then continue from there. The binding proteins required to get to the multicellular are only available to eukaryotes.

This would be basically the flow from the first cell to the end of the stage. We’d need to add the multiple patches play onto this. What do you think? Is that sufficiently structured that a beginner could play without getting overwhelmed?

We could also have a “freebuild” button in the main menu, rather than new game. When you press that you go to the editor and have unlimited mutation points to make a species and then the world you spawn into is fully populated with prokaryotes and eukaryotes, which basically means you can skip the early phase and just jump right into the meat of the game.

All feedback welcome. Does this sound difficult to build from a technical perspective?


That sounds like a really cool idea. Also right now the population system does split the population In half.


That sounds great! And I think that you should be able to go back to an immediate, living ancestor if you go extinct too quickly. A couple opinions:
The player should be given access to chemosynthetic proteins at first, not a whole chemoplast; chemoplasts should be gained by engulfing a bacterium with chemosynthetic proteins, and would be much more efficient than them,
Maybe new proteins could have a higher MP cost if you don’t have any in your cell currently, but then their cost would decrease depending on how many you have. This could be applied to all organelles and body parts, actually, because it seems easier to duplicate an already existing feature than evolve an entirely new one.
Are prokaryotes still going to be limited to 3 hexes? The player won’t really have room for a nucleus, which is 7 hexes, 10 if it includes the ER and Golgi, unless it starts out as a single hex which can be added on even if you already have three, which can then be upgraded further to a larger size.
Overall, this sounds like a good flow for the cell stage and doesn’t seem too overwhelming.


Having chemosynthetic proteins for prokaryotes sounds reasonable, likewise with metabolic, photosynthetic and nitrogen fixing proteins (-> mitochondria, chloroplasts, nitrogen fixing plastid). For other organelles it would be nice to have only one version which all cells can use (taking bioluminescence as an example) rather than having to double it up for not much gain. All feedback welcome.

I like the idea that new mutations cost more MP than making copies, it makes sense as it’s a smaller change.

I don’t think there’s a reason to limit the size of prokaryotes, here’s an example of a big one. Becoming a eukaryote would unlock a lot of new functionality which makes it very worth it.


Do we want a nitrogen fixing plastid for this release?

Also that’s very interesting , I agree we shouldn’t limit them now.


We’ve already got a lot of stuff for this release so I definitely wouldn’t want to hold things up for it. If all the other 3d models are made and working and there’s still time then it’s ok to add it.


What’s a nitrogen-fixing plastid? I’ve never heard it mentioned before.


It’s an organelle to do Nitrogen Fixation. Bacteria could have a protein, I guess it would be called Nitrogenase, to do this. A nitrogen fixing plastid would be a eukaryotic organelle which does the same thing (so basically if a eukaryote absorbed a nitrogen fixer much like absorbing a photosynthesizer to make a chloroplast).

The protein and the organelle would both make a small amount of ammonia from atmospheric nitrogen. Very useful to have if you are a slow moving photosynthesizer, for example, as it means you don’t have to hunt for ammonia in the same way (you’d still need phosphate though).



We could do like .5 ammonia a second or something though even that feels a bit large imo.


I think it should be balanced to take approximately the same amount of time to get enough ammonia to reproduce that way as the average cell moving around, for gameplay reasons.


Agreed, balancing all the new stuff when the time comes is going to be interesting