War is the wheelhouse of the Kagzar. It is their culture, their religion, and their favorite sport. War is seen as many things: tribute to their god, Stelo; a cultural ritual that cements their identity apart from the Jasemi and the dissident Kagzaren; a way of life for those who wish to commit to it; and just plain fun.
Many centuries ago, long before the Crisis, the Kagzar waged war for real. Before the Jasemi evolved into a separate species, they were a proto-Kagzar with incredible magic powers. These proto-Kagzar moved into the living spaces of other proto-Kagzar near the base of the rainforests, intimidating them with their great magical powers, forcing the native Kagzar to move into the plains. Strife quickly rose between tribes over the best herds of Pufbulo to hunt - it was the only reliable source of food now that the proto-Jasemi had moved them from their lands. War soon followed, with thousands of Kagzar dying in an attempt to claim as much land as possible.
Centuries moved on, and the wars subsided. The Pufbulo was domesticated, removing the need to battle over the most prime herds to hunt. Grass was bountiful across the plains, giving the domesticated Pufbulo plenty to eat. The need for war had passed - and yet, the Kagzar continued to battle. It was the most convenient way to separate themselves from the newly-evolved Jasemi; the Jasemi refused combat of any kind, and the memory of them pushing the Kagzar away from their original settlements still burned bitterly in Kagzar cultural consciousness. War was chosen as the official cultural activity of the Kagzar to give them a strong sense of identity away from the peaceful Jasemi. Some Kagzar - who would later evolve into the Kagzaren - did not approve of these battles and chose to restrain from participating.
War grew less and less bloody over time and eventually evolved into a form of religious ritual. Stelo, it was decided, needed bloodshed to be truly happy. Stelo especially wanted the blood of noble warriors who had proven themselves in battle. What better way to make Stelo happy, the Kagzar decided, than to make sure that only the worthy die in battle? Warfare quickly changed from real battles to mock-combat games. Swords and spears were replaced with wooden imitations, and the caste of warriors was invented.
Only Kagzar who were ready to dedicate their lives in totality were allowed to join the warrior caste. They would crop their ears short, cover their bodies in tattoos, and were not allowed to change their caste again. They would be given gleaming blades of bronze, and allowed to fight to the death with warriors from other tribes. Participating in warfare became a game of practicing being sacrificed to Stelo. Only warriors were allowed to die in combat - it is considered ignoble for a non-warrior to die during a battle.
Today, war is seen in much the way organized sports are on Earth. War is arranged between clans well ahead of time, picking out the best-trained fighters for the most virtuous fight. The objectives for each battle are chosen by both tribes - holding ground on an important piece of land, or capturing an elder from the other tribe, for instance. All war is waged with mock weaponry carved from wood, carefully kept blunt to avoid serious trauma. Only the warrior caste wield real bronze weapons. While the non-warrior Kagzar brawl it out, the warriors duel one-on-one to see who is the most capable fighter. Winning one of these duels adds to your honor, and dying in one ensures a place in the afterlife as a part of Stelo itself. The more duels you win, the higher a station is ensured for you in the afterlife once you grow old and slow and a new up-and-coming warrior kills you in battle. Quite frequently a new warrior's first kill is a positively ancient warrior who has grown too old to even hold a sword. So goes the cycle of Kagzar life and death!