with the development of complex behavior, sexual selection will appear, each mating partner will give a different discount, the greater the discount the partner gives, the more difficult it is to persuade him to mate with the player’s creature, females will choose who to mate with based on the principle of preferences, which are based on your species (for example, if your the species values strength, you must demonstrate strength) and in order for the player to be able to receive large discounts, he must spend DNA points on developing skills to persuade the other sex.
I am unsure if this belongs in the multicellular stage category, mostly since I am unsure when meiosis will be added to Thrive. Of course, the idea of principles of preference sounds like there might be a brain, but pheremones could work the same way, assuming that they work by showing how much energy an organism has to spend on producing them.
The idea of female and male is very reliant on biology evolving similar to the way it did in our world, which may not occur if evolution takes a different pathway. Of course, this idea relies on the ability for sexual reproduction to be modified, as seen in this thread. If it is not, then the only thing to be modified will be the organisms mind, as implied by the idea of principles of preference. Unfortunately, the proposed system doesn’t address the factor of what the preference will select for, or the performance of AI species also affecting the DNA of the player, assuming that the player doesn’t simply spawn as the child they produce. What I propose is that the player can select a change to be made to a part, or select an organelle, to be used as data for a preference that would give a discount to that change, and other related changes. The way this would work is that a player would right click on an organelle, tissue, part, or other, and select a button that makes it so that the part will be discounted next generation, with the understanding that this may also make it more difficult for the player to reproduce. In addition, the preference could also negatively affect other changes, or in this case, organelles, in terms of MP cost.
As mentioned, the simplest way would be to have an MP cost reduction, but this doesn’t explain what the preference would be, or how the player would represent it, unless it possibly works as a number that each organism has a number that represents how “fit” they are, and how much of an MP cost reduction they would have. If an organism has less than or equal to the amount of number that you have, then you will be able to mate just fine, though no MP cost reduction will occur. There could also be a punishment for mating with an organism with less number than you, in the form of an MP cost increase for doing so. However, if the player tries to mate with an organism with more number than them, then there will be a random chance of failure that gets higher the greater the difference between the 2 is. This makes a discount that is harder to get the higher it is, thus making for a rudimentary form of sexual selection, though there is the risk that reproduction relying on luck could be unfun. Alternatively, the player could choose whether or not to gamble reproduction, or to take a lower score for garunteed reproduction at cost of more MP being required to evolve, assuming that punishment is implemented.
In either case, whether complex or luck based, the player would be able to get an MP discount in the editor, with harder to get discounts being more valuable. Of course, this being implemented requires that Thrive first gets to the Aware (or multicellular) stage, which may happen soon, but not yet, as Thrive is still in the Unicelllular stage.