Rizkul are considered the most stealthy and aggressive kul out of every species currently on Threa. They inhabit the Starless Jungle as its top predator, terrorizing any creature to enter the trees. While many tales describe these beings as nightmarish creatures made of darkness materializing from the underbrush, in truth, they are medium-sized kul with a very lizard-like body structure. Their body is long and cylindrical in shape, with a flexible but relatively short tail for their body length. The tail is used to grip onto tree branches and trunks while climbing up and down the canopy.
The kul's neck is slightly shorter than other kul necks when compared to its body length, simply due to to the compact environment they live in. A body that is too bulky or lanky may get caught up in the various hanging vines and other hazards in the wilds.
To combat this crowded environment, Rizkul have evolved to be very stumpy creatures. While their chest is comparable to that of an Aezkul in overall size, the actual height of the Rizkul at the shoulder is much smaller, averaging between 1.8 - 2.0 meters (5'10" - 6'7") tall. Rizkul males are even smaller, nearly half the size of their female counterparts at 1.4 - 1.7m (4'7" - 5'7") at the shoulder. This is due to their leg structure. As mentioned earlier, Rizkul have a very lizard-like, crocodilian structure to their body. This means that their legs are very short, but thick and muscular, adapted for trudging through thick undergrowth or hoisting the creature up into the canopy. The arboreal nature of the Rizkul has led to their claws developing to be very thick and sharp, allowing them to hook into the thick bark of rainforest trees without breaking off the bark or the claw itself. Each paw harbors four digits tipped with these climbing claws, with the forepaws sporting thumbs to allow tighter grips on smaller branches.
Other adaptations include short horns, almost vestigial in nature, from their ancestors who once inhabited much more open areas. Some Rizkul bear no horns at all, as if the species is in the middle of evolving further. The scales on their body are very thick, sturdy, and broad, protecting the dragon from cuts and scrapes from the various thorns and other hazards lining the jungle. They do not overlap and simply interlock with little to no space between each scale, preventing debris from getting caught between them.
While the dragons do sport wings, they are very small, with a wingspan scarcely breaking the kul's overall length. They cannot support the weight of a Rizkul in actual powered flight and have far too weak muscles to lift it off the ground, even slightly. Instead, these small wings are now used to glide between the treetops. Rizkul launch off of the giant trees of the jungles using their powerful legs, then spread their wings to catch the air and allow them to hit another tree nearby without ever having to touch the ground.
Tree-based stalking is often used when hunting the dragon's prey. Rizkul do not hunt in a normal fashion, using teeth and claws. Instead, they have developed a very unique weapon; acid. Stored within a thick organ within the dragon's chest, near its spine, this acid is highly corrosive and eats away at all sorts of organic materials. Enough of it is powerful enough to cause dents and divits in solid steel. A specialized mucus lines the Rizkul's storage and delivery organs for this acid and its saliva nullifies its effect, protecting the dragon from its own weapon. However, all other parts of the dragon's being are fully vulnerable to its own acid, making it a very dangerous weapon to use in groups.
Due to this weapon, Rizkul can cause prey to drop dead from afar by accurately spitting a small stream of its acidic compound at it from the canopy, which quickly kills the creature if it spreads in the bloodstream. With Rizkul saliva nullifying the acid, the prey is save to eat for the hunter. The acid itself sprays from small openings in the roof of the dragon's mouth, which are covered with tight valves that only open when force is exerted on the liquid resting within the tubes connecting the openings and the acid gland.
Since hunting has devolved from fights of claws and teeth, the dragon's jaws have become rather weak over time, making them have possibly the weakest bite force of all dragons in Threa. Their teeth have evolved to be numerous and on the smaller side, needle-like in shape, and used for cutting flesh off of bone rather than breaking the bones themselves. While its claws are formidable, the being's physical build makes it hard for it to actually use its claws without exposing its vulnerable underside. Thankfully, the acid and natural stealthy behavior of these dragons is nearly always enough to protect it from any challengers.
Aiding their stealth is their coloration. Rizkul come in very dark shades of olive and green, with sparse deep browns and green-yellows popping up here and there. They sport markings that break up their outline against a dark background, manifesting in the form of leopard-like spots, stripes, patches, or any variation thereof. These markings are only ever darker than the base colors, mimicking the shadows cast from the canopy far above.
In stark contrast, their eyes are a bright yellow or orange with no visible sclera. Their pupils are large and round in shape to pierce the darkness of the jungle. While their distance vision is lacking, their middle-ground and near eyesight is very sharp and extremely good at seeing in near pitch blackness. These pupils narrow to very tiny slits when confronted with direct sunlight, which is near blinding to these dragons.
As mentioned earlier, Rizkul males and females are drastically different sizes. Until maturity, this is the only visible difference. However, female Rizkul develop a bright fiery blue stripe marking down their flanks once sexually mature. As females usually lead a tribe of Rizkul and do not hunt alone, they do not need the deep stealthy colors the males always adorn, and can thus survive with the bright stripe singling them out.
The Rizkul are highly suspicious and aggressive kul. Any Rizkul or Rizlin not in their tribe are immediately considered suspicious. Foreign kul are almost always chased out of Rizkul territory the instant they are seen. Within the tribe, however, Rizkul are much more open. They all tend to know the names and general personality traits of their fellow tribe members and, to a lesser extent, the Rizlin living among them.
These kul can be considered very vicious creatures - part for amusement and part for self-defense practice. Since they live in an area with abundant food but dangerous enemies, the Rizkul have taken killing as a sport much more than any other kul has. Large animals that other kul may never touch save for food are fair game for bored hunters. Oftentimes, the dead animals are left to rot in the muddy jungle floor, becoming food to the carrion creatures of the jungles.
Even more exciting than killing can be terrorizing. These kul love to jump through the treetops and spy on foreign kul or lin entering their territory, spitting acid in small amounts in their paths or sending herds of animals sprinting straight for them. They emulate strange gurgling screams in their throat to unsettle those that enter. Rizkul territory is essentially a nightmare come true for the unprepared.
The matriarch and her subordinates are the most intelligent of the Rizkul. While the males are more brash and aggressive, the females are cool and calculating, knowing how to manipulate others to get her own way. Due to this, many Rizkul clans end up being adopted by a Rizlin tribe, becoming one large multi-species tribe. The Rizkul generally tolerate the Rizlin, seeing them as a pest above all else, but the matriarch prefers to keep them around for the protection and free food they offer. Rizlin are handy in their own way and the undying dedication they offer to the Rizkul they worship due to their religion is of extreme use to territory-hungry clans of Rizkul.
Since Rizkul almost never know their own family, the concept of brother, sister, father, or really anything that isn't 'mother' has little meaning. Therefore, friendships are the strongest bonds a Rizkul can have. Earning one's friendship is a daunting task among the Rizkul and is essentially impossible for outsiders. Many Rizkul will have acquaintances galore, but very few have many others they consider friends. Furthermore, friendships are also really only common between the kul themselves; Rizlin aren't usually ever considered 'friends', but certain circumstances can cause them to be so, such as saving a kul's life.
Furthermore, the concept of 'friend' to a Rizkul is rather unlike bonds other species may form. Rizkul friends are characterized by tolerating each other more than the others and preferring the company of the friend over random Rizkul during any outward expedition. While a Rizkul exploring with another random male may leave the male for dead if it is injured, a 'friend' Rizkul may either dispatch the injured kul, attempt to find help, or pull it back to its own tribe if possible. Rizkul tend to only form friendships with others that are very similar to it in heritage, be it through blood relation or simple similarities. While the kul themselves are unaware of this, it is part of natural instinct to keep ones own genes going on in the species, even if they're only similar genes.
In Rizkul tribes, the head female is honored by every kul. She is almost never alone, flocked by eager hatchlings or determined suitors. As odd as it may seem to outsiders, she is considered a mother to the entire tribe, despite having no family bonds to all of them beyond her own hatchlings. The kul honor her as such and bow low to her whenever she addresses them. This is the only sort of structure and respect the Rizkul seem to show, as fierce competition and fights often break out among the various suitor males in other situations.
Meanwhile, Rizlin are seen moreso as pests than anything. Most Rizkul grudgingly acknowledge their gifts and the use they bring to the tribe - shelter, protection, tools, and so forth. However, they still often get in the way and seem to complain a lot more than the hardy Rizkul do, causing tensions and irritations between the two species. Overall, they get along well, as many have grown to need each other to survive.
Since females are extremely scarce, reproduction entirely focuses around them. One female is often courted and mated by many males during her fertile times, each male hoping to inseminate her. All males in the tribe try their luck at the head female if she permits them, with those that are denied often going to the subordinate females to try their luck there, instead. While the head female is gravid, the subordinates also get a lot more 'traffic', so to speak, as the males attempt to copulate with them instead.
The head female will not often refuse to mate with those of her own tribe unless they have recently done something to dishonor themselves or her, such as messing up a hunt or causing harm to another Rizkul. Otherwise she may deny kul based off of their current visible strength or recent performance in tribe activities.
Tribes only expand through reproductive means, as well. Male lone Rizkul will often sniff out female Rizkul over miles and miles of jungle. Once he finds her, he will ask her to join her tribe to add his blood to her line. It is up to the female to grant permission or no, with the final acceptance into the tribe being the copulation between the two kul.
Rizkul are laid in clutches of about five small eggs. Temperature decides their gender at this point, with heat creating more males and coolness more females. Due to the humidity and heat of the rainforest, many more males are born than females. Rizkul hatchlings are taken care of by the multiple male suitors to their mother, who is almost never around at the time of hatching. Female hatchlings are praised and coddled much more than males, who are seen as rather expendable in comparison.
Rizkul hatchlings grow at an average rate, reaching about half their parents' size at around five years old. They also develop their acid at this time. Due to this, five-year-old Rizkul are extremely dangerous to be around, even for their parents; the new weapon is seen as intriguing to the young ones and they want to test it out on every material they can. After a few months, this acid play calms down and the hatchlings begin to learn more survival skills such as stalking and hunting.
After another year, all male hatchlings are kicked out to survive on their own and, eventually, find their own female. Females, however, are taken in by the tribe to be raised to sexual maturity fully at eighteen years old. At that age, however, even the females are forced to find their own tribes rather than leech off of their mother's.
Females continue to live a more privileged life than males even in adulthood; since females are so rare, lone wolf males flock to them with wishes to breed and found a tribe of their own. Older females can attract ten or twenty males as well as some subordinate females to help raise and guard hatchlings - or busy the males when the leader female is gravid.
Males, on the other hand, live in their own in the wild for multiple years to build up their strength and hunting ability before hitting sexual maturity, also at age eighteen. Even after this mark in their life, they may still practice to ensure their spot in a tribe later on; there are enough males that females can afford to be picky with their suitors.
The Rizkul live in a very complex, very dangerous, but very lush ecosystem. Near the top of the food chain, there is not much for them to fear, but still enough to put challenge into their lives and prevent them from overpopulating the rainforest.
Rizkul live in the rainforest of Threa, the Starless Jungle, which borders the Aezrikka Zule along the south, the ocean to the west, the savannah to the east, and the deciduous forest to the north. It is lush and wet year round, with rain often pouring down from above. Various trees are constantly in flower or fruiting throughout different times of the year. The terrain itself is rather flat with slow rolling hills or valleys. Occasionally, sharp cliffs may arise and prove a hazard to the unwary kul.
Rizkul are primarily carnivorous, but they may digest the fruits of the rainforest, as well. Precious vitamins and minerals not found in meat can be found in these fruits, helping enrich the kul's diet.
Rizkul hunt medium to large game, mostly, as it is plentiful through the rainforest. Hunters are sent out in duos or trios to capture a few large prey animals and drag them back to the tribe for feasting every so often. Occasionally, the kul may find the nests of other animals that live in the rainforest; a delicious treat to any Rizkul.
The large venomous snakes of the rainforest are the biggest issue to the Rizkul. These monstrosities have mastered the art of clamping a Rizkul's acid-spitting mouth shut to administer their own venom into its veins. These snakes are often killed on sight by hunting parties for fear of what may happen. Other large predators may fight for territory or compete for game with the Rizkul, but nothing matches up to these oversized serpents when it comes to fear or danger.
Rizkul originate from ancient Trezkul who were originally ancient Sozkul who had moved inland from the coasts. Over time, these ancient Sozkul shifted their coloration and developed a weak venom. These ancestors of the Rizkul split off into three groups, each moving to different parts of the globe; one staying put, one heading north, and one heading south. The band that headed south into the rainforest are those that developed into the Rizkul; their greens darkened, they developed camouflage, and their venom became spitting-venom before developing into a corrosive acid.