Since species can interbreed, it's safe to assume that foals will not always take after the species of their dam - but their species isn't random either. How is the species of a foal determined? By genes of course! The species gene is made up of two alleles, one from each parent. If the foal inherits two different alleles, the rarer species is always recessive. To quickly refresh, Crosspyro are 'Rare', Merroyal and Aerokni are 'Uncommon', and Woolyfur and Highlander are 'Common'. Merroyal are slightly rarer than Aerokni and Woolyfur are slightly rarer than Highlander. However, species with the same rarity ranking are considered co-dominant and which species the foal become is somewhat random with a slight bias to whichever species is more common.
The alleles are represented by the first letter of the species name, so that would be: C, M, A, W, and H. Whichever is acting as the domaint will be listed first. Ex: WH would be a Woolyfur, while HW would be a Highlander. To assume the form of the Crosspyro species, a foal must have CC genes, since C is recesive to anything else. This means that a foal must get one copy of the C allele from each parent! A CC Crosspyro bred to a WW Woolyfur will never produce a Crosspyro, but bred to a WC Woolyfur it could.
Of course, after many generations of breeding, most equines do not have 'pure' genes, other than Crosspyros which are always pure. That means that many horses carry an allele for a species different than the one which they visibly are, especially in the cases of the common species. Because of this, a Highlander crossed with a Highlander may be more likely to produce Highlander foals, but if one or both of them carry other alleles it's possible for them to produce other species.
Pattern mutations are what you'd think of as marking or coloration patterns. These include some very standard, natural horse patterns, some patterns that might be found on other animals, and some unnatural patterns. The list is forever growing as new pattern mutations happen from time to time! Some are believed to be genetic, while others appear to happen at random. It's entirely possible for an equine to have multiple patterns, though some may be more predominant than others.
Standard face/leg markings are common and not considered a mutation. (You can use them on any horse for free.) They are usually white but can also be a lighter shade of the base color. Shading similar to the dark points of a bay are also common.
* = Available for free on created horses. (Includes Tuddles.) Those not marked with a * can only be obtained through hatchings, contests, or possibly the marketplace.
Genetic
- Paint: These are markings like what you would find in Overo/Tobiano horses. They can range from a lighter shade of the base coat to pure white. Only occasionally do they happen in colors that vary from the base coat. These markings usually have distinctive edges and can vary from rough to smooth.
- Frost: This is very similar to paint markings in that it usually creates white patches across a horse's body - essentialy, Sabino. However, these markings tend to have a lot of speckling or roaning along the edges and may have a lot of semi-transparent spotting within them as well.
- Blanket: This pattern is what you would think of as a blanketed Appaloosa. It creates a white (or light) blanket over the hindquarters and occasionally back of the horse, either solid or with speckles of color showing through.
- Spotting: This results in spots (usually at least nickle sized) across a horse's coat. White spots are most common, but they can be any shade of the base color (lighter/darker). Very rarely, spots may be an alternate color. They can range in size up to quite large spots, almost always circular or oval in shape. They never uniformly cover the body and can vary in density from clusters to just a random spot here and there.
- *Roan: Roan causes white flecking throughout the body of a horse. It does not extend onto the head or lower legs. It can range from very faint flecking to very dominant flecking (making the horse almost white). Some roans will also have frosted manes and tails. Rarely, roaning can be an alternate color from the base coat.
- Calico: This results in patches of 2-3 colors across a horse's coat. They are usually only standard colors for the species and most often contain some white. It may look similar to a paint pattern, but the patches are usually smaller and more dispersed across the body. It only shows up in females of species other than Highlander, but can be carried by any horse.
- Primal: This results in dun-type markings on the horse's coat. They can be in any color (not just natural colors) and almost always show up a shade or two darker than the base coat. This ofte includes a dorsal stripe (always), leg barring (almost always), ear rims, cobwebbing, and guard hairs. Shoulder stripes, face masks, neck shadow, and barbs (from dorsal stripe) may occur.
- *Dapple: This is exactly like dappling in real horses. It usually results in lighter or darker dapples than the base coat. This is not to be confused with grey in real life - it does not lighten with age. While this may have genetic ties, it does not distinctively appear within family lines and shows up at random.
- Peppering: Not to be confused with spotting or roaning, this results in a speckling of small dots across a horse's coat. The spots are larger than roaning and may not cover the whole body, but are not as large as spotting. They are most similar to Fleabitten markings in real life. Colors are usually a darker shade of the base coat, but may occasionally be lighter as well.
- Marble: This results in a coat that looks very much like marble. There will be grains of dark and light usually taking on vaguely linear patterns. It can sometimes look quite similar to dappling, but is distinctive because it is more linear.
- Brindle: This is very rare and has no distinctive genetic ties. It results in striping (white or a lighter/darker shade of coat) primarily down the barrel of the horse, similar to the rib lines. It can extend into the neck or hindquarters as well.
- Elemental: These are very unnatural, random markings that are often somehow tied to a horse's elements. They are similar to what you'd normally think of as 'tribal' markings and can range from a few subtle swirls or lines somewhere to a coat that is almost entirely tattooed with elemental symbols.
The list is short, but there are many more to be discovered! These types of mutations may sometimes be similar to abilities but are not considered mystical in nature. They can include physical differences or unique types of talents.
Genetic
- Slow-Growth: Horses that have this gene will grow much slower than is expected. Most of them do not mature until well beyond 4 years, sometimes not until they are 5 or 6. They will reach sexual maturity later as well. Due to their slow development, they cannot support a rider until they are older, sometimes 2 or 3.
- Deviate: A deviant is born belonging to the 'wrong' element(s) - in other words, their abilities will be those common to a species other than their own. But really...is the element wrong or is the spirit in the wrong body?
- Under- or Over-sized: These are simply horses that mature to be either too tall or too short for their species. This is more than just a couple inches - enough that they'd be obviously odd-sized.
- Atypical Color: These are horses who exhibit a coat color that is not standard for their species. This could include something like a green Highlander, black Merroyal, or blue Crosspyro.
- Gembear: This mutation only happens to Merroyals. A Gembearer will have a brittle horn and hooves that crumble off, producing small gems. Their horn and hooves usually end up multi-colored with this mutation.