From EncyclopAtys
During the Great Swarming, the Kitin invasions haunted the minds of the Homins, and even the bravest warriors shivered at the presence of these monstrous creatures who swept over the people of Atys. Joint Karavan and Kami forces pushed the Kitins back into the depths of the Prime Roots, but the Powerful could not completely chase the members of the Swarm to the surface. Since then, the Kitins have been moving around the Bark.
The Kitins are present in all the regions of the new colonized territories. They are adapted to different ecosystems, boring into the soil and hunting animals to feed their colonies. It is, therefore, difficult for the Homins to not cross their paths. Some Kitins are not aggressive at first, or only attack when they are bothered. But memories of the Great Swarming are too vivid to allow peaceful cohabitation, and confrontations are frequent, especially since the Kitin invasions are not over...
Attacks have, in fact, been launched many times on the new Homin territories, the Swarms destroying everything in their path to take over that geographic zone. Once their goal is achieved, the Kitin patrols criss-cross the zone to destroy all threats on the newly conquered territory. All members of the Swarm are aggressive during the invasion, the workers becoming as fearsome as the soldiers. The kipees, who are ordinarily peaceful, attack in waves, with groups of kipestas flying by their sides and spreading over the smoldering death. The fierce kirostas pierce shells to inject terrible venom. Large kipuckas often lead invasions, protected by kinrey soldiers who fight to the death.
In order to fight this scourge, the people deploy scouts who are charged with informing the warriors, who are brave enough to confront them, of the Kitins' movements. Makeshift camps are built to house the garrisons sent by the Homin governments. Political differences tend to be put aside during invasions, and it is not unusual to see enemy clans fighting the monsters of the Swarm side by side. Rewards are offered to the hunters who bring back trophies, and the mobilization of the guilds is encouraged to bring down the great Kitins who are leading the invasions.
The sages have been asking themselves many questions about the Kitin chiefs. Are they just animals, or are their adversaries as intelligent as the Homins? Do they feel hatred, are they simply obeying a survival instinct? The Swarm's objective remains unfathomable.