Yeah, it would be cool if when giving a cost you could set it to remain the same.

I tried doing clever ♥♥♥♥ like making an event that triggers when the player has a particular trait unlocked, and gave them that trait at the beginning of the game. But strangely, neither of the event variables that involve genetic drift actually turn it off. It's actually really annoying and makes it difficult to plan out anything.

There is an event outcome "genetic drift = True/False" ... but it doesn't work!

However you can cancel it out for the most part, by controlling "genetic drift multiplier".

Genetic drift is a multiple based on global infected percentage, so you can negate it by applying the opposite sum:


Setup a repeating monthly event (event counter threshold = 28, times event can trigger = -1, reset event counter when fired = checked), then define the following outcome: "Genetic drift multiplier = 1 - (0.5 * infected percentage)"


However that has some biases, because genetic drift is modelled on a curve, but events can only model straight lines. What you'll see, therefore, is slightly higher costs around the middle of the game, which settle back to normal at the start and end of the game.

You may also see small variations throughout the game, where genetic drift has increased but the 28-day event hasn't come round yet. You could increase the frequency (eg. 14 days), but that might exacerbate another issue:

Repeating events effectively lock-out the cycle, so if you use them:

- any other repeating events with a lower counter threshold will stop this one from firing
- any other events with a higher counter threshold will never fire

So basically, avoid either of those things if you're using this event. The higher the frequency, the more likely this is to be an issue.

Though come to think about it, you might just be able to set "genetic drift multiplier = 0" (with a single event right at the start).

Can't remember whether that would work, or whether it would just set all prices to zero (or just not work at all).

I tried setting the genetic drift multiplier to 0 but that didn't work either. And as far as the event outcome that sets genetic drift to true/false, I don't think that's intended to turn off genetic drift; I think it's intended to shut off a trait's ability to enable it, like in instances when a trait or event modifies a separate instance of genetic drift intended for separate lines of traits. But regardless, you're correct, it doesn't seem to do anything. This is quite a conundrum. The ability to disable genetic drift is something I'd like to have in the future. That and the ability independently modify the costs of traits throughout a scenario. I think that could be very useful in instances where a government is using drugs to inhibit your disease.

I posted the "genetic drift" switch as a bug a while ago, but I didn't get much more than a shrug in response :-) But there aren't separate instances of genetic drift -- genetic drift is a single logarithmic scale which multiplies the value of all traits from whatever they would have been otherwise. Here's what the scale looks like on a graph: http://www.brothercake.com/Ref/drift-default.png

Did you try the repeating event approach from my first post? I know this works, because I've used it myself.

I took the idea a stage further and used it to create randomly fluctuating DNA costs, as described in this post: https://steamhost.cn/steamcommunity_com/workshop/discussions/-1/626329187083663311/?appid=246620#c622954023416368691

But you could go further still, and create very precise costs, by creating specific multipliers at different times in the game.

The basic principle is that a genetic drift multiplier of 1 will double the cost of every trait when 100% of the world is infected; or a multiplier of 2 will quadruple it. Here's another graph with some sample figures: http://www.brothercake.com/Ref/genetic-drift.png

That's what I used to work out how genetic drift is modelled, from which I extrapolated the best-fit line that would cancel it out: 1 - (0.5 * infected percentage)

What I meant was that I thought if you had two different traits, both affecting genetic drift, but with different multipliers, the genetic drift switch could be turned off for one trait without affecting its multiplier or the other trait and its multiplier. But as you said, that's incorrect.

I did try the repeating event approach, but it's fairly janky unless that's the only event in use and it wasn't as accurate as I'd like it to be. I suppose since the genetic drift switch exists, one could assume that it will be functioning properly at some point in the future. Until then I suppose I can make due with making scenarios the common way (#tragic).

Yeah it has biases because it's a best-fit straight line trying to compensate for a curve. But without a log() function to work with, that's the closest you can get.

Traits don't affect genetic drift at all, it's purely a factor of global infected percentage.

I wouldn't count on the genetic drift switch ever working. The fact that it's not fixed now probably indicates that it's not a simple fix, for something that's quite a niche feature. But you could try reporting it to the bug thread, maybe that will create some impetus :-)

Out of interest -- why do you want to turn it off anyway?

Oh, I thought for sure you could string together traits and events to affect genetic drift. I guess I was thinking of something else.

I suppose I wanted to turn off genetic drift because I'm just strange. I wanted to be able to more accurately control the player's progression throughout the scenario. Majority of the game has a sort of vague chaos to it, which makes a lot of the game random and adds a degree of chance to other aspects. Which, I understand is part of the point of the game. But having control over what's happening is the point of being a designer. And it's difficult to plan something out when there are so many other factors that could change at any point during the game. So I suppose a simpler way to say it would be that I simply wanted to have a little more control over how the player progresses through the scenario.

This seems to be a common problem with me though. I'll often times look into making a mod for something and change my mind later because most games are designed with a one-way mindset, and that makes it difficult to think outside of the box. That's not necessarily negative, of course. It's just not always easy to hang shelves on something that has a limited amount of pegs.

If you can't change the pegs, use a different material for the shelf :-)

Or something ... the point is, if you can't change the mindset of the game, then you need to change the mindset of the designer ;-) I don't agree that the point of being a designer is to have control; the point of being a designer is to mediate between humans and interfaces, and that doesn't require full control, it only requires influence.

Web design is a good analogy -- web designers have very little control over how their design is percieved, because users can change how they view web content (increase font size, apply a high-contrast theme, change the size of the window etc.). So web designers have to let go of the sense of control and work with the fluidity of the medium.

Coming back to Plague Inc -- there's still a lot you can do within the constraints of the game's mechanics, it's just a case of flowing with them, rather than fighting against them.

In the case of genetic drift, I would argue that getting rid of it will be of little benefit, it will just make it easier for players at MB, and that's not really a good thing. When you're planning out how the game should progress, you can test at Brutal to see how it behaves without genetic drift, then test again at MB to see the difference. If you need to plan for the difference in costs, then genetic drift is predictable, so you can do that; you just can't expect it to be the same at MB as it is at other levels.

What I generally do is plan a strategy at MB, and make it insanely hard, like, only just possible. Then when you play at lower levels, it's easier :-)

Perhaps I have some sort of biase. I've been designing games for several years, but recently new creative projects such as the Workshop have given people more intimate access with games and their inner workings. This is both good and bad. The bad part is that players now believe that they're designers and are now somehow on the same level as the designers of the game. The good part is that game designers like me have now been forced to adapt. For example, in order to make a good Plague Inc scenario, I can't rely on the freedom that comes from designing something of my own. I'm forced into constraints and limitations that make me think differently about design. So when it comes to designing scenarios for Plague Inc, it's less about building shelves and more about making nifty trinkets for the shelf that's already there. Which is obviously not the same as designing the shelf, or even the entire wall. But it does provide the same satisfaction and personal accomplishment, even if it may not be to the same degree as building a shelf or a wall.

So in some ways I'm very appreciate of the limitations that games like Plague Inc provide. I have very much enjoyed our conversation thus far, and I am also very appreciative of your time, thoughts and willingness to contribute. I actaully haven't even thought of MB yet, but trying it on MB first does seem like a rather good idea.

Yeah I hear you :-)

I'm a programmer, and I went through a similar process -- initially excited by the potential, then quite dismayed by the limitations! But eventually I came to round to realise that, it is what it is, and if I just accept those limitations and work within/around them, then it's a lot more enjoyable. And of course, the better you understand where the limits are, the more you can start to push their plasticity :-) A lot of it is just trial and error!

You might enjoy / find inspiration in something I've been working on. A scenario called "After The Plague", where I've been trying to see how far I can push the concept of event-driven scenarios. It's only about 2/3 finished and it's not in the public workshop, but if I add you as a friend then you'll be able to see it.

Originally posted by brothercake:

I posted the "genetic drift" switch as a bug a while ago, but I didn't get much more than a shrug in response :-) But there aren't separate instances of genetic drift -- genetic drift is a single logarithmic scale which multiplies the value of all traits from whatever they would have been otherwise. Here's what the scale looks like on a graph: {LINK REMOVED}http://www.brothercake.com/Ref/drift-default.png

Just released a fix to the genetic drift. Sorry if we missed it the first time round!

Much appreciated, my lovely cookie.

Originally posted by Ndemic Tom:

Just released a fix to the genetic drift. Sorry if we missed it the first time round!

Oh right, nice one :-)