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Effective breeding requires a solid understanding of the mechanisms involved.  You need to understand what traits are, how the values for each trait interact, and how they're passed from parent to child.  This section covers those basics.


Traits are those features of the cat which determine some attribute.  While traits can control anything, not just visual appearance, but other facets, such as behaviors, for KittyCatS! they only control visual appearance.

We're concerned, here, with those traits which can be bred.  That is to say: for this discussion a trait is a feature of the KittyCatS! game which is under your control.  While gender and size are, in the strictest sense, traits, since they are controlled by the game engine and unaffected by your choices, we'll ignore them for this discussion.

The traits are:

  • Fur
  • Eye Color
  • Eye Shape
  • Pupil Size
  • Shade
  • Tail
  • Ears
  • Whiskers Color
  • Whiskers Shape

In KittyCatS, traits are independent.  That means, the factors controlling one trait have no effect upon any other trait.

While all cats have all nine of these traits, for this discussion we'll use the stylized line drawing of a cat to represent just one of these.

Trait ValuesEdit

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Each trait can have a number of possible values.  In KittyCatS!, each value is given a name. 

New values are added often, so it's not possible to present a full list here.  Examples, however are Small pupil size, Ocicat Lilac Lynx fur, and Illume shade.  For a complete listing of all known trait values, and when each was introduced (or, at least, discovered by breeders), refer to the History maintained by Deerylou.

While the same name may appear in a number of traits, within a given trait, however, that name is unique.  For example, Mysterious eye shape not the same as Mysterious ears, and both are completely different from Mysterious tail.

Individual trait values are interchangeable and distinct.  That means, no matter where you see it, the name for a value represents the same value.  In other words, if you have two cats, each with the Russian White fur trait value, the Russian White factor in one is identical to that same factor in the other.  And, given a third cat with the Russian Black fur trait, Russian Black is completely different from Russian White.

Trait values are independent.  Nothing about one effects any other.  So, even though the word "Russian" appears in both Russian Black and Russian White furs, those values have nothing in common.  There is no "shared Russian-ness".  The relationship between Russian Black and Russian White is the same as the relationship between Russian White and Genesis Coco .. you can't take the Russian-ness and Coco-ness and make a Russian Coco.

When viewed in-world, it can appear as if Shade and Fur interact.  While, yes, it can appear they do interact, sometimes with desirable results, this is not the case as far as breeding is concerned.  So, while a Russian White with Illume shade might appear quite different that a Russian White with Natural shade, the Russian White-ness of both cats is identical and independent of their shade.

Finally, trait values are ordered.  If we compare any two trait values with the same name, they are always equal.  And, for any two trait values with different names, one is always "more dominant" and the other always "more recessive".  Saga's Charts present the best information currently known about these relationships.

For this discussion, we'll use just four values.  Ordered from most-dominant to least, these are:

  1. Black
  2. Red
  3. Green
  4. Blue

This number was chosen because it allows the representation of all possible cases.  Remember, however, that the actual number of values for a KittyCatS trait can be quite different.

There will always be at least two values.  Any fewer and the trait would never change (and we'd not call it a trait, or be interested in it).  Eye Shape, for example, only offers Curious and Mysterious.  Often, as with Fur and Eye Color, there are quite a few possible values.

Four values were chosen for this discussion because we'll be looking at what happens when two parents produce an offspring, and four values is the maximum possible in that case.

Each cat has two valuesEdit

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When we look at a cat, in-world, what we see is the final result.  The question is: how was that result obtained?

Internally, each cat has two values for each trait.  What we see in-world is the result of comparing those values and selecting the more dominant of the two.

In the image, we have three Black cats.  Internally, each has two values.  Here, Red means "more recessive" .. it could be Green or Blue, but the result will still be Black.

Many times, we draw breeding charts showing which of the two internal values came from one parent, and which from the other.  But that is not important.  Nor is the order in which we draw the colors.  All that matters is that there are always two values, and the more dominant of those is what determines the final appearance of the trait.

Each parent passes one value to the offspringEdit

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When it comes time to make a new cat, the parents each randomly choose one of their two values for each trait and pass it to the offspring.

The odds controlling which of the two values the parent passes are "even".  In the example, it is equally likely the left parent would pass Black as it is likely it would pass Red.  Red was chosen simply as an example.

The selection of a value for one trait is independent of the selection of a value for any other trait.  Which value was selected from Fur, for example, has no bearing upon which value the parent chose to pass to the offspring for Whisker Color.

At this level, gender is not important.  In the example, we have two Black parents.  Which is the Mother and which the Father does not matter.

Remember, also, order (in the image) is not important.  So, even though the Red offspring is drawn with the Red internal trait value on the right, it would still be Red if the Red were on the left and Green on the right.