The plague beast rests within the depths of the den after such a long walk. Feeling well-rested, it stands up and starts its evolution, the fur on his neck is modified into quills, and the muscle surrounding it twist and form knots to fire-off these quills when needed.
His claws grow longer, as well as his fingers, developing a fifth, shorter finger, an opposable thumb, on his sets of arms.
His scales become bigger and thicker, forming dense plating on his body. The tail develops more muscle, and becomes as thick as his arms, now being able to swing it freely instead of needing momentum.
The plague beast calls forth its subordinates with a deafening roar that can be heard troughout the plains and into the mountains. Soon after, the vermin gather around the den, awaiting orders.
The plague beast comes forth, his fangs like kitchen-knives, his horns thicker and durable, its plated skin shining an earth-brown color with red accents, the muscular tail swinging its blade, ready to chop if needed, and the body, far stronger than anything seen, the muscular arms seem capable of ripping trough stone with the mighty claws, wich have been modified to be made of bone, its strength rivaling that of the perfectly smooth and shining rocks that were seen on the mountain.
The apex predator however, was far from perfection, it called forth the vermin, and voraciously ate hundreds of them. As he ate, troughout his back grew spikes that would shred the flesh of any if he fell on them. His body became muscular, his legs thicker, his chest more prominent, his arms grew even larger, as well as increasing the size and sharpness of his rending talons. His eyes perfected the vision he had, now able to hunt trough the night and even close-in his view on specific targets. His vision was perfect. His body, however, was not. The plague beast yearned perfection, it felt sick, knowing the things he lacked and couldn't achieve.
The beast saw the vermin, and decided to give them a second gift: Will-fully mutations.
The beast spat out the biological matter from his mouth and to each of his children, each one of them mutated to better suit their motives, those that were able to fly grew larger, gaining a greater wing-span and razor-sharp talons. The rodents were able to change their tails into a stinger, to pierce trough the thick hide of other foes, as well as being able to change it into a small mace to crack their bones.
These were no longer vermin, as they devoured the weakest and grew in size, the birds were the size of a harpy-eagle. While the rodents ressemble more a tibetan-mastiff with a vaguely rat-like head and a long tail.
The plague beast ordered his off-spring to reproduce, his kingdom lacked servants. And so, his children did as ordered, the beasts retreated to the forest and started mating. The sound of the beasts howling was found to be particularly distasteful to the plague beast, but he had to bear it for his own sake.
He retreated back into his den, the ravine closed behind him any possible entrance. When he reached the center of it, a vine dug deep within the earth in search for water. Upon finding an underground lake, it proceeded to siphon water from it and onto the surface and in a leaf modified to be thicker and solid, meant to hold liquids. The plague beast created his personal fountain of water. Delighted with its work, it created a seat of smooth and soft vines near the fountain to rest, and opened a shaft to the heavens to let light seep onto his new throne and himself.
The plague beast sat upon its throne, bathing in the sun. Resting...