You know, it's been a while since we had any new Lizardman breeds proposed...here's three.
Tree Skinks
While all skinks are naturally quite good at climbing and scurrying about with great agility, the tree skinks take this predilection to the next level. Tree skinks are noteworthy not only for their large eyes and slightly longer snout, but also for their lithe limbs, large hands and feet, and the enlarged gripping pads on the end of each digit that enable them to cling to smooth and solid surfaces no other lizardman can find purchase on. Their limbs are strong, but double-jointed or even capable of reverse-jointed nonsense that makes other skinks wince in pain to contemplate. As a result, they are less suited for heavy labor and industrial concerns, as they simply cannot carry repetitive heavy loads on their more delicate limbs. Sometimes, they even drop to all fours to scuttle about on their hands and feet as quadrapeds, claiming that this is the 'easy' way to carry loads on their back, as it distributes force more evenly amongst all four of their locomoting limbs. Their tails, however, long and prehensile, are useful as well to grasp and hold objects. They love to participate in grand towering construction projects, clinging with feet or tail to any handhold they can find, and focused on carving or assembling their work, hundreds or thousands of feet above the ground.
In point of fact, the very name 'tree skink' is a misnomer. This breed is not new-far from it, for many of the first generation of Slann beheld them at work long ago, toiling on the great polar gates in space. In microgravity, the skink's adaptations make more sense. Their dark nictating membranes protect the eyes from solar glare, their limbs are all workable as arms and hands, their balance and lack of motion sickness, all point to their true origins as orbital construction workers.
That being said, they are well adapted to any three-dimensional environment. With rebreathers or the appropriate blessings, they are adept swimmers and divers, on forested worlds, they clamber about like squirrels, and in urban mega-conglomerations, they can squeeze through holes and appear unexpectedly from any vent or passageway, or even cling to ceilings as they maneuver into position.
Feathered Skinks
Feathered skinks are, by and large, the largest pain in the rear and greatest headache the Slann will ever create for themselves. While skinks might be confused and argue about an order, Kroxigors might dig a trench four meters deep and 4 megameters long, and Saurus might stand around dumbly if they don't understand what is being asked, only feathered skinks will, cheerfully reinterpret the orders of a Slann, take what they are not given, and achieve results that the Slann did not intend, but yet which still align with their own desires.
The mage-priests-kings have only themselves to blame. They ordered that the magic of the Coatl be woven into the lizardmen after all, that the blood of the skinks should be made to run ever so slightly hotter. Not Warmbloods, certainly not that hot but....warmer. More free and loose, more capable of independance and change. Artisans, technicians, musicians, inventors, scribes, and in wartime, commandos and scouts, all of these can benefit from the feathered skinks amongst their numbers. Therein lies the problem and the reason that the Slann will never be rid of their problem caste.
Feathered skinks emerge from the spawning pools with only white or brown down clinging to their soaked bodies, but as they age their feathers grow more complex. They move from simple fibers to branching structures, to veined feathers to asymmetrical feathers that look almost flight worthy in the oldest chiefs and priests. As they age, they also grow more and more colorful, with new patterns developing as well. And as their feathers develop, so to do their minds, and their ability to...experiment. The very creative ability that makes them peerless artists, sub-creators, and clever devils to their enemies makes them insufferable to everyone around them as they begin to constantly tinker with and tweak the way things are done. There is no greater agent of small c chaos and generator of subculture and divisions within Lizardman society than the feathered skinks. But, by the very same token, the things that make them outsiders in their own society make them absolutely peerless in dealings with outsiders.
Saurus Jockeys
The Saurus jockey is the smallest, least physically capable breed of Saurus that the lizardmen spawn. They are inferior to their standard cousins in physical combat, and for good reason. Saurus jockeys are made to ride and drive, not to march. Their bodies are lithe and flexible rather than heavily muscled so they do not impose too greatly on their mounts, so they can ride longer and harder than traditional Saurus. While they are credible marksmen, their true purpose becomes apparent when they are place behind the reins or controls of a larger beast or vehicle. All-jockey crews are the hallmark of a well-prepared lizardman armored force, and even as mounted cavalry, aback cold ones, they are less demanding and wearing on their mounts than traditional Saurus are. Inside tanks, scout cars, aerospace fighters, and the gunnery mounts of starships, they are consistent, competent and aggressive operators.
Interestingly, the Jockey phenotype is not one that a Saurus must inhabit for it's entire life. Instead, the phenotype can be switched on and off, with the brain and body restructuring either for a life as a user of rides, or as a user of personal armor and weapons. This process takes time and must be commanded by a Slann with magic, but can be done en-mass to large formations all at once.