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Creature Labs provide a wide range of useful developer information through the Creature Labs web site.

These pages are designed to help you find the information that you need, no matter what kind of Creatures developer you are.

The information required to build real living systems is held in a molecule called DNA (deoxyribonucleic acid) – a long string of individual instructions, named genes. One of these strings of genes is called a chromosome, and a complete set of chromosomes (humans have 46, Norns have one) is called a genome. Creatures has a similar, albeit simpler, system that is comparable to DNA which we call Digital DNA (D-DNA). In nature, each cell carries a complete set of genes to build an entire organism. In Norns however only one D-DNA strand is kept for each creature. The genes in Creatures code for organism structure, with genes describing the chemical reactions, physical structure, brain layout, instincts and so on. The behaviour of your Norns is not specified by genes, instead, just as in real life, behaviour emerges from the structure. In the normal course of events, Norns breed, and a new creature is created from the D-DNA of the two parents ith some random mutations to make it unique.

The Genetics Kit is a complex piece of software, and requires patience and an investment of time in order to achieve the best results. This help file does not attempt to teach you the biological principles of genetics, but we do recommend some excellent books and papers should you wish to learn more:

Real living systems are incredibly complex. Your DNA contains the instructions for synthesising the amino acids necessary to construct the proteins that eventually make your cells—all ten trillion of them. You have around 100,000 genes, or instructions, and each of the cells in your body carries a complete copy of them. Your genes code for structure rather than specific behaviour. There is no gene that allows you to walk to work, for example. This is something that emerges from the systems created from your DNA. Whilst in Creatures it has not been possible to model genetics at a protein level, we have stayed true to the principle of genetics—in that we code for structure, not behaviour.

The Creatures system consists predominantly of three parts, all of which are genetically specified, and subject to mutation over generations:

Users already familiar with the Genetics Kit for Creatures 2 may wish to look at a summary of the major changes.

The Genetics Kit for Creatures 3 operates substantially the same as the original product for Creatures 2, so you will find the user interface familiar.

Many new features have been added to aid in the development of large genomes and handle new features in the Creatures 3 system such as neuro-emmiters and brain tracts.

Some general points for experienced Genetics Kit users:

The Genetics Kit allows you to display and manipulate the genetic codes that describe Norns, Ettins and Grendels, and generate new eggs and Digital DNA (D-DNA). In summary, you can:

The Genetics Kit imposes some limitations on how some genes can be edited. These limitations are designed to prevent the construction of organisms that could not live in the Creatures world.

Bear in mind that you are tinkering with the structure of life, and that genetics dictates a creature’s structure, from which behaviour naturally emerges. If you reduce the structure, you’ll reduce the behaviour. This means that if you are planning on using the Genetics Kit to create immortal Norns that do not need to eat, or that can give birth in seconds, then you’re barking up the wrong tree. By removing genes such as those in the immune, reproductive or digestive systems, you will make stupider Norns. If you really want to make super-Norns, you would be better off improving the genetic structure, and enhancing the component parts of the Norn physiology, such as the digestive system. By doing this you can open new possibilities and new structures, out of which improved behaviour could emerge.

The D-DNA of your initial Norns, i.e. those for the eggs in the Hatchery consist of 810 genes. It is likely that by increasing the gene count substantially, or increasing the neurone count, you will slow your program down. You will need a fast computer to run Norns with a couple of thousand neurones (a "generation one" Norn contains about 970 neurones).

It is possible to specify systems genetically that the Creatures application cannot build because they are either impossible, or were never intended. Should this happen, check carefully that you have all critical genes that you need before reporting the issue as a bug. Also, see Notes on creating genomes from scratch.

The Genetics Kit consists of a number of pages for manipulating D-DNA, and injecting the results into the Creatures world. Through the menu you can access specialised on-line help:

Click here for a reference table of all menu items.

Genetics Kit cover-page. Version is shown bottom right, and a button for loading a genome appears at the base of the title image. This button mirrors the "Load Genome" menu option on the File menu.

Shows Genetic Summary of different gene types and brain composition.

The frame shows a summary of the currently loaded genome. It summarises the genetic makeup, and total quantities of each type of gene—also showing the exact number of male or female specific genes.

The value in this column of the Genetic Breakdown frame shows the difference in gene count between a template Norn and the currently loaded genome. This is based purely on gene type counts rather than an individual nucleotide comparison.

Shows Genetic Summary of different brain gene types and brain composition.

The top frame breaks down the brain structure into individual lobes, and shows critical information concerning each lobe. This includes the Width and Height in neurones, the total number of neurones present, Update times and the state rules. Click here for more information.

The bottom frame breaks down the brain structure into individual tracts, and shows critical information concerning each tract. This includes the connectivity, Migration, Update times and the state rules. Click here for more information.

Main Gene Editor window allowing the complete gene list to be viewed and modified. Genes can also be deleted or created from scratch.

Primary Gene Editor page. All editing, creating and deletion of genes takes place on this page. Genes can be selected by clicking on them. A gene must be selected before using Edit Gene, Delete Gene or Rename Gene. No selection is required to create a new gene using New Gene. Specific genes can also be edited by double clicking on them in the gene list. Right clicking on them will bring up a context sensitive menu:

In summary, the buttons and their purposes are:

Gene name information is not stored inside the genome itself, as that contains just the genetic data. Instead, all gene names (called "captions") for any given species (Grendels, Norns, etc.) are stored in a special file called "species.gno". When you create your own Digital DNA, new "GNO" files are made and stored in the genetics directory for each genome you make. If this cannot be found, or is separated from the original D-DNA, then the default (species.gno) is loaded and a warning issued.

The organ view window shows all the organs in the genome, and allows the display of individual genes (Receptors, Emitters and Reactions) by organ.

This displays all the genes that are found in Organs (receptors, emitters and reactions) inside the appropriate organ. Genes can be edited from this page in two ways:

Display and edit the complete Creatures global chemical list.

Shows a complete list of all chemicals in the Creatures biochemistry system, along with their numbers and descriptions. These come from a file called "chemicals.txt" that is stored in the Genetics Kit folder.

Chemical processing is done numerically inside Creatures, so this naming procedure is only to make the system more human friendly. Deleting the name of a chemical will not remove any genetic reactions that use that chemical! If the chemicals.txt file cannot be loaded, chemicals are represented numerically.

Actions can be initiated from buttons, or using the context sensitive menu (Right mouse button).

All the above options and an option to save changes to the chemical list are available from the pop-up menu. Click with the right mouse button:

Before you can view the levels of your new chemicals in the Biochemistry Set applet, you will have to edit the 'chemicalnames.catalogue' file in your creatures catalogue directory, and save it.

Please note that any new reactions will be working regardless of whether you have edited the chemical catalogue. The catalogue is required only so the Biochemistry Set is able to assign names to the chemical numbers.

The chemical text name list is not saved automatically. You must use the pop-up menu, or the "Advanced" menu. You will, however, be prompted on program exit if there are unsaved changes. Saving the chemicals does not make them available to view inside Creatures—you must edit the chemical names in the catalogue file (see above).

Display and edit the complete Creatures global pose-name list.

Shows a complete list of all pose names in Creatures, along with their numbers and optional descriptions. These come from a file called "posename.txt" that is stored in your Creatures folder. Pose names are global, so altering this list will affect all creatures. New poses can be added, and existing ones removed.

Pose processing is done numerically inside Creatures, so this naming procedure is to make the system more human friendly. If the "posename.txt" file cannot be loaded, poses are represented numerically. Pose names are used only in the Genetics Kit to make it easier to understand. Creatures uses the numerical representations.

Adding a new pose will require new genetics to represent the pose in addition to creating a name and description here.

All the above options and an option to save changes to the pose name list are available from the pop-up menu. Click with the right mouse button:

The pose name list is not saved automatically. You must use the pop-up menu, or the "Advanced" menu. You will, however, be prompted on program exit if there are unsaved changes.

Display and edit the complete Creatures global brain-variable-name list.

Shows a complete list of all brain variable names in Creatures, along with their numbers. These come from a file called "variablename.txt" that is stored in the Genetics Kit folder. Variable names are global, so altering this list will affect all creatures. There are eight lobe variables and eight tract variables. You can use these variables in SV rules to store values and perform calculations. You can not add or delete from the list but may change the names in order to make SV rules more meaningful to the task you encode them to perform.

Variable processing is done numerically inside Creatures, so this naming procedure is to make the system more human friendly. If the "variablename.txt" file cannot be loaded, variables are represented numerically. Variable names are used only in the Genetics Kit to make it easier to understand. Creatures uses the numerical representations.

All the above options and an option to save changes to the pose name list are available from the pop-up menu. Click with the right mouse button:

The variable name list is not saved automatically. You must use the pop-up menu, or the "Advanced" menu. You will, however, be prompted on program exit if there are unsaved changes.

Inject new eggs and scripts into Creatures.

The Export page interfaces the Genetics Kit to Creatures. You must have Creatures 3 installed and running in order to use the functionality on this page.

There are a number of advanced features present to work with macro scripts inside Creatures 3. You should click here to see information on the Creatures Developer Program and how it can help you understand macros.

In its simplest mode, this page is used to inject new eggs into the Creatures world from the currently loaded genome. These eggs can then be hatched in the incubator. Click here for information on hatching eggs.

If you make changes to the AutoScripts, you will be prompted if you wish to save them when you exit the Genetics Kit.

The Advanced Options dialog is available from the Advanced menu:

Plot Chromosome Map plots a graphical representation of the currently loaded genome, and is available from the Advanced menu:

The Chromosome Map window can be kept open whilst using other features of the Genetics Kit.

There are a number of basic procedures that will help you with operation and understanding of the Genetics Kit. These are:

The instructions for making living systems are encoded into their DNA (and in the case of most viruses, RNA). DNA stands for deoxyribonucleic acid (for RNA, drop the "deoxy" from the beginning) and is made up of chemical instructions for manufacturing proteins—the building blocks of living cells. A complete set of instructions for making one single protein is called a gene.

Collectively, the genetic instructions required to make an entire living system are called the genotype, and the resultant life form exhibits the phenotype.

Genes are joined together in a long string of DNA, punctuated by special markers. This is then wrapped into a giant super-helix called a chromosome. Chromosomes can contain many tens of thousands of genes.

Creatures contains a biological modelling system that borrows many of the metaphors and concepts from biology. Digital DNA (the system in Creatures) is a digital equivalent of biological DNA. The primary differences are:

More information is available on the Norn Genome, the Grendel Genome and the Ettin Genome in Creatures.

A "Generation One" Norn (from an egg in the Hatchery) consists of approximately 810 genes. Unlike human beings, who carry two of each gene (one from the mother, and one from the father), a Norn carries only one of each gene. Some of these genes are specific to a certain sex, so in a male Norn, the female genes will be carried, but not actually used. The "Generation One" Norns have 17 female specific genes, and 9 male specific genes.

When Norns breed in the wild, the genomes from the mother and father are laid out next to each other, and genetic material from one parent is exchanged with material from the other. The points along the genome where the exchanges take place, and the number of genes exchanged are random and occasionally there will be "crossover errors" which could result in individual genes being lost or duplicated. This process generates two new genomes, one of which is male, and the other is female. During natural births, the choice of which of these to use is random, whilst a Genetics Kit birth leaves the choice to you, based on which gender you would like the new creature to be. The result of this is that a new Norn egg inherits a combination of genes from the father and mother together with some potential mutations and errors.

Norns have 19 different gene types, each containing varying amounts of genetic information. Genes are broken down into four basic categories:

1. Brain Gene. Definition of brain lobes, tracts, neural dynamics and dendrite properties.
2. Biochemistry Genes. Chemical receptors, emitters, neuro-emitters, reactions, half-life and initial concentrations.
3. Creature Genes. Stimulus, species, appearance, poses, gaits, facial expressions, instincts, pigments and pigment bleeds.
4. Organ Genes. Organs contain biochemistry components such as reactions, emitters and receptors.

The Genetics Kit allows all of these Genes to be viewed, and most can be edited. In addition, genes can also be either added to the genome, or removed entirely. Click here for a summary of the different gene types.

Grendel Digital DNA is similar to Norn D-DNA. Many of the genes and structures are identical, but Grendels are differentiated by their instincts, and stimuli. The initial Grendel genome used in Creatures is stored with a moniker starting with "g". A caption file to label the purpose of each gene is also kept for each.

Ettin Digital DNA is similar to Norn D-DNA. Many of the genes and structures are identical, but Ettins are differentiated by instincts and stimuli. The initial Ettin genome used in Creatures is stored with a moniker starting with "e". A caption file to label the purpose of each gene is also kept for each.

All operations inside the Genetics Kit require a valid genome to be present. As it is very difficult to create a genome from scratch, you’ll probably wish to start from one of your existing Norns. The Digital DNA for every creature you have ever had (including Grendels and Ettins) is stored on your hard drive. Once a Creature is in the game, it has a unique moniker, just for that Creature. You can find the moniker from the last page of its agent help in the game itself. The genetics files of living creatures are in the Genetics directory of your world's directory, underneath My Worlds. The Attic directory in your world directory contains the genetics files for Creatures which died a while ago.

The monikers are made up as follows:

ggg is the generation number. It is the higher of the generation numbers of the two parents plus one. E.g. The child of a gen 1 and gen 6 Norn is gen 7. The child of a gen2 and gen3 is gen4. ffff is the "friendly name" for the moniker - From the feel of the word, it should be pretty simple to see if the genome is Norn, Ettin or Grendel. The four sets of five characters are the moniker itself. This is a combination of several seeds, creating a unique string just for that Norn.

To load the genome of a specific creature:

1. Load the Genetics Kit and click on the "Load Genome" button. A file loading dialog will appear. Use the dialog to locate the ".GEN" file for the creature whose DNA you wish to load.
2. Click "Load".
3. That is it! You now have that creature’s genome loaded into the Genetics Kit.

Genomes can be saved using the File Menu.

There is a restriction to the names you can use to save genomes under certain circumstances. To understand this issue, it is necessary to explain how Creatures accesses genomes: A macro command is used to instruct Creatures to create an egg or a creature from a named moniker. The Genetics Kit automatically does this for you when you create eggs from the Export page, so if you are doing this exclusively then there are no restrictions as to the filename you can pick.

However, for Creatures to be able to access your new genomes independently of the Genetics Kit, you must follow the following naming convention:

If you save it in an alternative place or with an invalid file name, neither Creatures nor the Genetics Kit will be able to use that genome as a parent when eggs are created. This is because both Creatures and the "moniker of other parent" text box on the Export require a valid moniker.

The Digital DNA for the initial eggs provided in the Hatchery are stored in the Creatures 3 "Genetics/" folder. The files are named after the type that they are the genome for. For example, the moniker that starts with "norn.bengal" is the bengal tiger Norn.

New eggs can be created on the "Export" page of the Genetics Kit. Eggs can either be created as "virgin births", where only one genome is used to make the egg, or a second parent can be specified. Creatures must be running to use this page!

This is because you have too many Norns on board the Creatures 3 space ship. Remove some by exporting them. The incubator may take a few minutes to switch back on again.

It is possible to create genetic clones of any Norn or other creature you have had.

You will now get an egg inside the space ship by the incubator. This egg will hatch naturally after around 4 minutes. You can speed up this process by putting the egg in the incubator.

The Genetics Kit allows you to create new eggs by "breeding" existing genomes. This can be useful for experimentation purposes.

You will now get an egg inside the space ship by the incubator. This egg will hatch naturally after around 4 minutes. You can speed up this process by putting the egg in the incubator.

Genetic manipulation and experimentation tinkers with the very building blocks of life, accelerating the process of evolution, and compressing millions of years worth of mutations into an afternoon’s work. Along the way you will create many imperfect creatures, unable to prosper in the Creatures world. In these cases it is often more humane to also accelerate the process of natural selection by removing them yourself.

There are many ways of removing creatures from the Creautres world that do not involve pain, the easiest of which is to simply export that creature using the Creatures menu inside Creatures 3.

However, the Genetics Kit does contain a quick way of eliminating objects and creatures from Creatures 3. Click on the Export tab. You can remove a Norn by running Creatures, selecting the Norn you wish to remove, and then clicking on the Remove Selected Norn button:

Any Norn that is removed in this way is deleted permanently.

The macro interface means that you have the option to create your own macro scripts that can remove Norns from the space ship (or any other agent, for that matter).

Genetic Engineering is a complex task, even in Creatures where the genetics are less complex than their biological parallels. It is beyond this help file to teach genetics to every reader, although we do recommend some good books. Two basic concepts are required before working with Creatures genes:

This section of help looks at the processes involved in:

There are three different ways to edit a gene. All of them require you to select a gene from the Gene Editor first. Then, either:

When a gene is selected for editing, a window will open. The appearance of this window depends on the gene type. For example, editing a Chemical Reaction gene opens a window like this:

There are 19 different gene types. All gene windows share some common controls:

Broken down into their five categories, they are:

As well as a common header and a Cancel button, each gene also has a Notes button that allows you to enter a more detailed description of a gene. This is in addition to the gene name, and is saved in the caption file (.GNO files) along with gene names. To access the notes page for a gene, click on the appropriate button inside any gene window:

This opens the gene notes window. You can use copy and paste to insert text that includes basic formatting. Try pasting from Word, or WordPad for example, or simply type directly into the window. Here is the gene notes page for a progesterone emitter gene:

Using Cancel to abort a gene will not cancel any changes you have made to the detailed descriptions.

To create a new gene, click on the New Gene button from the Gene Editor page:

If you are starting from a clean genome (i.e., no genes loaded), the Genetics Kit will ask you if you wish to create a species gene (the only compulsory gene). Read the notes before trying to create your own genome from scratch.

If you are adding new genes to a genome that contains at least one gene, the following window will be opened:

Clicking on the drop down box will reveal a complete list of gene types that you can create. These fall into four categories, Brain Genes, Creature Genes, Biochemistry Genes and Organ genes.

You can use the Create button to make new genes whilst leaving the new gene window open. This allows many genes to be added at once.

As a demonstration of the Genetics Kit, here are the instructions to creating a green Norn:

It is possible to use the Genetics Kit to create genomes from scratch. This is a highly complex process, and it is possible to build genetic structures that could cause Creatures to fail.

In almost all cases, it is desirable to load an existing genome and work from there until you are sure you have learned enough to consider building genomes from scratch.

Should Creatures crash as a result of loading a genome you have created, spend some time ensuring that the basic systems you would expect in a living system are present genetically. If you are sure that they are, and there are still problems, then we would like to hear from you.

Creatures has 19 separate gene types divided amongst four separate groups. These groups are: Brain Genes, Biochemistry Genes, Creature Genes and Organ Genes. All gene types share some basic header information:

The gene types and their descriptions are shown in the table below. Type and sub-type numbers are shown in parentheses after the name:

Organs were a new feature in Creatures2. Just like real-life organs, they contain biochemical functions, and can be damaged by disease, and repair themselves. In a generation one Norn there are 21 organs, although one of these is female-only. The more organs a Norn has, the more ATP it will use up.

Just like the other genes, the organ genes can be mutable, allowing Creatures to accumulate new organs for new functions. The gene appears like this:

The "Clockrate" determines how frequently the contained biochemistry will be updated. The further to the right the slider bar is, the more frequently the biochemistry will be updated. It is possible for a receptor to speed this up, or slow it down.

The "Organ vulnerability" sets how fast the Long Term Life Force moves towards the Short Term Lifeforce. The lower it is the more resistant the organ will be to damage (see below for a more complete description of this system).

The "Lifeforce start value" determines how sturdy the organ is at birth, and how much damage it can take before it dies.

The "Biotick start" is a way to co-ordinate the genesis of organs during development, so their functions switch on in the right order.

The "ATP damage coefficient" defines how dependent on ATP the organ is. ATP is the energy source for chemical reactions, receptors and emitters, and when it runs out the Creature becomes unconscious, and the organs start to degrade, being injured at a speed determined by their damage coefficient.

Organs allow biochemistry genes to be regulated in groups based on their common function. An organ will "contain" and regulate all the biochemistry genes following it in the genome, up until the next organ gene. The organ clockrate has a locus which receptors can attach to, and so it can be regulated according to a chemical level for instance. This allows reactions to be sped up or slowed down to maintain a constant chemical concentration, and deal with fluctuating conditions.

Organs can be in a healthy or damaged state, determined by their Short Term and Long Term Life Force values. Organs can take damage from diseases or physical injury, lowering their Short Term Life Force, and producing Injury chemical as a signal to the immune system. When Short Term and Long Term Life Forces are apart, they move towards each other at a certain rate. The rate at which Short Term Life Force moves is generally faster than Long Term Life Force, and is open to regulation through a locus. This allows for organs to heal, at a rate which can be influenced by the biochemistry.

If an organ’s Long Term Life Force falls to zero the organ is declared dead, and the biochemistry it contains will never be updated again. In this way Creatures can lose some functions before others. For instance, it is possible for a Norn to catch a disease which kills their reproductive system, rendering the Norn infertile, but otherwise healthy. Once an organ has died there is no way to bring it back to life.

To increase the rate of healing, each organ has a locus called the ‘Repair rate’, which a receptor can attach to. The effect of this locus is to regulate the rate at which Short Term Life Force returns towards Long Term Life Force. In hatchery Norns this locus is regulated by prostaglandin, which is produced by the bones in response to Injury chemical.

There is one brain organ per creature, which contains a number of brain lobes, specified in the lobe genes. The organ gene is responsible for specifying the physical structure that holds the brain, and is the target of any injury to the brain.

In Creatures 3, the Brain Genes are divided into Lobes and Tracts. Lobes are collections of neurons with a common processing rule and in a similar way Tracts are collections of dendrites with a common source lobe, destination lobe and processing rule.

The processing rules are called SVRules. For both lobes and tracts, they have an Initialization and an Update component. The Initialization Rule is called on neurons and dendrites newly created (and also on dendrites that have just migrated). The Update Rule is called every ‘tick’ (about 4 times a second in Creatures) to calculate the new state of neurons, the new state of dendrites and also for dendrites to pass information to and from their source and destination neurons.

Defines general properties for this brain lobe, and has the common mutation controls. The positioning and dimensions of the brain lobe can be specified here, also a colour for display in the Vat Kit. The Lobe ID is a four character word which uniquely identifies the lobe.

This page contains the common mutation controls and the Update Sequence information identical to its counterpart in the Lobe Gene. Note that the when the "Initialization Rule runs always" flag is set the Initialization Rule is no longer processed on newly migrated dendrites.

Connectivity

State Variable Rules (or SVRules) are genetically defined functions that are used throughout a brain lobe structure to control most aspects of synaptic and denritic behaviour, as well as to compute a neuron’s state.

State Variable Rules are composed of interpreted opcodes and operands. Each SVRule expression is designed to be interpreted extremely fast (as each neuron’s state needs to be calculated, as well as other synaptic behaviours such as the dendrite relaxation functions, for example), non-brittle and "fail-safe"—genetic mutations must never cause syntax errors.

SVRules can compute new state values in many ways. A considerable amount of the possible functions go well beyond the present needs of the brain model in Creatures, giving great scope for alternative brain structures.

SVRules for brain lobes are defined on the various pages of the brain lobe gene. When a State Variable Rule is edited, this window appears:

The SVRule can then be edited by using the drop-down boxes. The expression can consist of up to sixteen opcodes and operands. During processing, at each stage in the rule the interpreter keeps a particular value in mind, called the ‘accumulator’. In input lobes (i.e. those that the game engine feeds information into), this value is initialised to be the input for each neuron.

To aid more complex modelling and processing, each neuron (and dendrite) actually has eight variables available for information storage. For neurons the main ones are Input, State and Output. For dendrites (on the learning tract) the main ones are Short Term Weight and Long Term Weight. You can find a full list (which you can also edit) under the Variables tab on the main Genetics Kit window.

The rule above is taken from the C3 Norn genome from the ‘visn’ to ‘move’ tract. Each dendrite fires its movement neuron according to how much its vision neuron has changed. In detail:

1. The accumulator is put equal to the (absolute value of) the source neuron state we’re connected to.
2. The (absolute value of) the difference between this value and the dendrite’s last signal is put into the accumulator.
3. This value is attenuated by 0.8508.
4. It’s added to...
5. ...and stored in the destination neuron’s input.
6. The (absolute value of) the source neuron’s state...
7. ...is stored as our last signal for next time.

Please note: If you press Ok on the SVRule window, and then Cancel on the gene window, any changes you made to the SVRules are not cancelled!

Instincts allow creatures to be taught that doing a particular action given a certain situation is either bad or good for a particular drive, without the creature having to go through the experience itself. This allows important concepts to be "pre-taught" to Norns, Ettins and Grendels to affect their initial behaviour.

Instincts are used for many purposes. These include teaching Norns to retreat from other Norns when overcrowded, or to do something when bored and eat food when hungry. A typical instinct gene may look like this:

Instincts are processed when creatures sleep. If a creature does not sleep, its instincts will not be learnt.

During sleep, Creatures detaches the brain from any outside stimulation. The sensory inputs specified in the Instinct gene ("When this is true" frame, in the picture above) are then fed directly into the creature’s brain. The action specified in the instinct gene is then encouraged to fire by means of an input to the "verb" lobe and then training impulses are sent through the response ("resp") lobe. This training causes dendrites from the drive lobe to the combination lobe to be strengthened and the weights increased according to the degree to which the drive rises or drops, as specified in the instinct gene.

The creature will then form neural connections that are likely to respond should the scenario specified in the instinct actually arise when the creature is awake. This allows scenarios to be presented to the creature’s brain, in advance of them occurring in real life.

Many instincts switch on at different life stages. Instincts are used to influence and encourage mating behaviour, for example.

An instinct will not guarantee certain behaviour in a given situation, it can only influence and encourage, as it will integrate itself with the existing neural structure the creature has.

The biochemical modelling system inside Creatures supports 256 arbitrary chemicals, each of which can vary from being not present (a level of zero) to maximum concentration (a level of 1). To help keep track of these chemicals, each can be assigned with a name and description. These names are then used to select chemicals in the Biochemistry Set, and also here in the Genetics Kit.

Out of the possible chemicals, just over half are used in "generation one" creatures. Over several generations, it is possible for some of the other chemicals to come into use by mutation.

New chemical names can be assigned in the Genetics Kit using the Biochemistry Page, and then used for new chemical reaction genes. You can also edit their names and descriptions. Be careful when deleting chemicals, as you may lose the ability to see them in the Biochemistry Set if they were already in use.

New objects and agents can also make use of any new chemicals.

Creatures supports a total of 256 different "poses" for creatures. These are numerical representations for the positions that creatures can get into in order to interact with their environment. Pose 77, for example, describes the body position for death. A total of 170 poses are used in first generation Norns. The Genetics Kit has a specific page for editing and viewing the pose names.

Adding a new pose name will not create a new pose. A new pose must be specified genetically. The pose naming system simply provides a method for assigning human-friendly tags to pose numbers.

For new poses to be valid, appropriate genes must also be created. The pose sequence requires each body part’s position to be specified numerically, a task made much simpler by the Creatures Pose Editor.

For poses then to be used by a creature, they have to either be incorporated in a gait, or used by a macro script that acts on the creature.

In Creatures 3 there are 6 facial expressions with IDs as follows:

Each facial expression gene votes for the expression it represents, sleepy etc, in the following way: Firstly, the overall strength of its vote is governed by its Weight under the General section. Secondly, facial expressions get points based on whether their drives mentioned in the form are high or low. In the picture below you will see that it represents expression 5 (sleepy), has a middling overall weight and drive weights of 0.3 on both Tiredness and Sleepines. So extra points are given to this expression (up to a maximum of 0.3 per drive) if the Norn is tired or sleepy. If the weights were –0.3 instead points would be awarded (again up to 0.3 per drive) depending on how not tired and sleepy the Norn is.