Hybrids do not have any sort of specific look to them considering they can come from various lineages. Their physiology varies wildly from tiny and furred to gigantic and scaled; to try and describe them as one would be like trying to describe the entirety of kul as one.
However, there are some common themes shared among all hybrids. The colors of parents will always mix to produce the hybrid's color no matter the color 'limitations' of the original kul. For example, a race that can only be hues of blue may mix with a race that can only be hues of red. These parents could produce a purple hatchling which is entirely out of both of their original color ranges. A hatchling cannot, however, develop markings that are not mixed from or inherited from one of or both of their parents' ancestry.
While it is possible for two different types of kul to mix and produce a hatchling that looks almost exactly like one parents' species, this is very uncommon and highly unlikely. It is much more common to produce a hatchling that has a mix of both species' traits and colors, looking very foreign to another pure-blooded kul. The scent of a hybrid is also very easily discernible from the scent of normal kul, as most species have a very specific recognisable scent. This makes it very easy for any creature with a keen enough nose - primarily other kul - to hunt a hybrid down.
Anatomically, hybrids are still dependent on their parents' genes. Two stout and strong species will produce a stout and strong hatchling and nothing else. On the other hand, a stout and strong kul with a short and thin kul will produce anything within the range of stout and strong to short and thin with all the advantages and disadvantages it might apply to the newborn's life.
Hybrids may only ever inherit the racial 'speciality' of one parent. For example, a Blazkul/Aezkul mix will either have a very strong flame or specialized wing muscles for more perfected flying. This rule is largely based off of how the traits of each race work. The chest capacity used by a Blazkul's fire-making organs directly conflict with the space required by an Aezkul's muscles for flight. A Hozkul's air purifying second set of lungs would take up the exact same spot that an Aezkul's fire-making organs would. If a hybrid 'tried' to have both of its parents special traits, it would have a pretty terrible time dealing with half-functioning organs from both sides and would not make it past the first year due to failure and subsequent necrosis of the afflicted organs.
Beyond this one rule, hybrids essentially may inherit anything from their parents. A Hozkul/Aezkul hybrid could have the wings, muscle, and fire from an Aezkul as well as the hulking size and muscle of a Hozkul. Of course, they are still subject to the rules of physics; this kind of hybrid would find it impossible to get off the ground no matter the size of its wings.
A list of species-specific racial traits are as follows.
- Large chests with thick muscles for flight
- Small near-vestigial fire-producing organ Azkul:
- Cannot hybridize! Blazkul:
- Large well-developed fire-producing organs
- Extreme heat resistance Hozkul:
- Air filtering organ
- Extremely thick-set muscular structure; completely disables use of any wings Izkul:
- Anti-freeze blood and extremely efficient metabolism Rizkul:
- Acid producing organs for spit Sozkul:
- Blubber Trezkul:
- Venom glands Truzkul:
- Furred coats
Races from parents will generally pass down to hybrids if they include markings or specific visual traits. A Firehorn Blazkul producing a hatchling with an Aezser Aezkul would likely produce a hatchling with colored and unique horns as well as the Aezser racial markings. Beyond this, there's nothing classifying hybrids as specific races unless one wishes to consider the kind of mix they are a "race" of the "hybrid species".
The general instinctive behavior of a hybrid is generally a 50/50 mix between their parents. If a very aggressive species hybridizes with one that has a calmer disposition, the resulting kul would likely be touchy, but not outright aggressive. A lot of the kul's behavior depends on how it was raised, however, and many hybrids end up taking to the aggressive and defensive end of the scale due to how they are received in nearly all of Threa.
Social behavior heavily depends on how a hybrid is raised. A hybrid living under Blazkul rule will likely be very militant while one raised under Aezkul rule will likely have an appreciation for knowledge. It depends upon the values instilled in them from their parents and society. Outcasted hybrids, however, tend to go their own way, developing their own unique personalities and views on life. Those that live in nature their entire lives tend to revert to more primal ways, forgetting language and resorting to primitive growls much like the Trezkul.
Reproduction really depends on the hybrid. A hybrid is sterile if its parents were not from the same branch of the evolutionary tree. From the ancient Azkul came three big groups of kul - the oceanic branch (Sozkul and Izkul), the forest branch (Trezkul, Rizkul, and Truzkul), and the extremity branch (Blazkul, Aezkul, and Hozkul). Within these branches, hybrids will come out sterile and are easier to produce. However, between branches, all hybrids are completely sterile and hard to produce in the first place.
Hybrids can also breed with each other to produce viable children if they originate from the same branch as well, but cross-branch 2nd generation hybrids will also be infertile. So, for example, an Aezkul and a Blazkul can produce child one. Child two comes from a Blazkul and a Hozkul. Child one and two can breed and are potent. However, child three comes from an Aezkul and a Rizkul. This child is completely sterile and cannot breed. Child four comes from a Rizkul and Trezkul. Child four can breed with child one and two, but their children will be sterile. So on and so forth. A pure-blood can also breed with a hybrid within its branch to produce sterile children.
Hybrids are generally born only one to two at a time no matter the original clutch size of their parents. In many societies, hybrid eggs are instantly smashed after being laid. If they do manage to hatch, however, a hybrid will likely be ostracized wherever it goes. Even in more accepting societies like Treztown, hybrids are looked upon as misfits and weirdos. Hybrids generally must seek solace amongst other hybrids or among others who have had or understand interspecies relationships.
Due to the sheer possibilities of hybrid origins, there is no true overarching comment to be made about their ecology.
Hybrids can live really anywhere in the globe considering the amount of possibilities that exist. However, most hybrids end up gravitating towards accepting societies like Treztown. Others who do not find a home in a society will likely end up living off of the land in the wilds, alone and feral.
There are three major places hybrids tend to congregate; the Aezrikka Zule near the Aezkul, Treztown, and a hidden enclave far, far in the north hidden in the Taiga. One other place that they may go to, albeit rarely, is the Sokan Empire. There, they offer protection in food in exchange for their service as a mount in their army.
Since all kul eat meat, it is only logical that hybrids eat meat, too. However, their preferred kind of meat depends on their parents. Those in the oceanic branch will likely eat fish and various sea creatures while those from the others will prefer red meat. Mixes between the oceanic and other branches generally produce a child that has no preference between either, but can easily digest both without much issue.
The biggest enemies hybrids have are the kul that produced them. Most societies are very unaccepting of hybrids and will banish or kill them on sight, seeing them as tarnished versions of their pure blood.