Brainstorming

Base Concept: Eight generations ago, the first "Merger" was accomplished. A Merger is a symbiotic union between a spirit and a special "breed" of human called the Tyrael (Chosen). The Tyrael are revered in society because they are capable of performing the Merger, which in turn grants them the power of the spirit they merge with allowing them to perform magical feats. These powers start off in an infantile state but as the bond between the spirit and Tyrael grows stronger, so does the Tyrael's development and enhancement of the spirit's powers. The Tyrael will also gain access to more powers from the Spirit as they grow stronger together. The other factor that makes a Tyrael special is that they have the innate power to remain dominant in the Merger while a normal human possessed by a spirit, would have no control. A Tyrael has a longer lifespan and stronger/better natural attributes when compared to a human as well.

For roughly 3-4 Tyrael generations, a Merger only occurred when a Spirit found and chose a Tyrael to its liking. A ceremony was performed in order to ensure a smooth Merger. Once the Merger was completed, the Tyrael would cease to be a Tyrael and would become a Kotada, the title and "classification" given to a Tyrael who was bonded to a spirit. This bond would remain until the death of the Kotada at which point, the Spirit would chose to either rest, regain its independence, or choose another host. Within the Kotada, there are 3 different classifications based off of the "purity" of their bloodlines, which typically also speaks to the strength of their spirits. These are Common Kotada, Nobility Class Kotada, and Royal Class Kotada. Royals tend to only breed with other Royals or Nobility Class Kotada, this improves the likelihood of producing a Tyrael progeny. The Tyrael offspring of two Kotada inherits some of the power of the parents during the pregnancy. This is also affected by the strength of the bond between the parents and their respective spirits. While it is rare, there have been cases where the bond is so strong that if the father dies prior to the child's birth or if the mother dies during childbirth, then a Spirit has merged with the descendant of its previous Kotada.

It should be noted that not all Kotada + Kotada unions produce Tyrael offspring. There are often cases where two Kotada even two Royal class Kotada produce a human offspring. Those human progeny are often "exchanged" between the ruling houses of the Crests. Meaning a human nobility family that produces a Tyrael offspring will send their child to live with a Kotada nobility family and a Nobility Class or Royal Class Kotada couple will send their child to live with that human nobility family. While humans may choose to keep their Tyrael offspring, a Royal Class couple will most always send off their "failures" since Royals who produce multiple human offsprings are considered weaker and less worthy.

The Catalyst - a little over 3 Tyrael generations ago
Above was how things worked until a war between two of the Crests forced the desperate apprentice of a shaman whose village was caught in the middle of the conflict to attempt something long considered taboo and unthinkable. When one of the strongest warriors in the village was killed during a siege, his spirit having grown to truly love the village over the decades chose to lend its power to another Tyrael of the village. Since a shaman performs the rites of the Merger Ceremony, both the shaman and their apprentice were ineligible. The apprentice was known to be one of the strongest Tyrael in the village and an obvious choice for the one who would be able to tap into the spirit's powers fastest. Still, the law was the law and it was there to prevent a corrupt shaman from attempting to amass too much power. It was never broken because it was a law given to the Tyrael from the Ruling Council of the Spirits when the first Mergers were performed.

As the elders deliberated and the army continued taking losses, the apprentice took matters into his own hands. The spirit was being kept in the temple in order to heal it quickly and try to strengthen its powers. The apprentice encountered the Spirit and asked what should be done. The Spirit knowing the law and the apprentice knew the dilemma and told the apprentice that the law has never been broken and it is one that should never be broken. The Spirit told the apprentice that they would have to have faith that the Tyrael chosen to be his Kotada would be strong enough to protect the village. The apprentice knew who would be chosen and knew that the Spirit's optimism was misplaced, so with no witnesses, he did what he felt needed to be done. He began to perform the Merger Ritual himself. The Spirit could not encourage or condone what was being done, but he also could not escape as the healing process rendered him immobile. The apprentice failed five times before he finally succeeded.

While the Merger process was being completed and the apprentice was unconscious near the altar, the Shaman returned to find the spirit missing and her apprentice there. It was obvious what happened. It could have been covered up if the elders were not with her. They ordered her to expel the spirit from her apprentice and perform the ritual for the Tyrael they had selected. The apprentice woke up while the shaman defended him and with the powers of the Spirit, lifted into the sky. His words upon awakening have become legend. "I will accept my punishment AFTER I save our people and our village. Until then, pray that I was right and you were wrong about who should be merged." The apprentice flew out of the temple and headed straight for the battlefield. His ability to tap into the Spirit's powers were remarkable and unprecedented. It was as if he had somehow matched his will to that of the spirit prior to or during the Merger. The apprentice managed to help his village defend itself and force the enemy to retreat. The other faction that was approaching from the other side of the village had rumors of a powerful Kotada in the village and elected to travel around instead of attempting to pass through it or capture it for strategic positioning. He used his powers to help repair damage done to the village and even heal some of the wounded. The Elders knew that they could not punish him, so they forced him to give up his dream of becoming a Shaman. He protected the village for years until retiring with his family.

That is the tale of the first Domination. It would not be the last. Word escaped from the village of how a Tyrael was able to conquer and take over a spirit. What was done only in desperation and necessity became an obsession to those with "weak spirits" seeking to conquer stronger spirits. For nearly an entire generation, those who tried failed until a noble warlord of one of the Crests figured out why so many others had failed. Once the secret was learned, he used it to form his own organization to stand in defiance of the Authority. They became known as the Brokers. Over the two following generations, they practically perfected the art of capturing an unbonded spirit, extracting a spirit from their Kotada, or more importantly to a lot of their clients, implanting the essence and/or power of a spirit into a Kotada. What they had learned is that except in the rarest of cases, a Kotada's spirit becomes so ingrained in them that dominating another spirit will merely allow them to absorb their power, but a frog who conquers a wolf, will not become a wolf, but merely a stronger frog.

Government System:
The world is controlled by a psuedo-government known simply as "The Authority" who decree the laws which are then implemented and enforced by the Seven Great Factions known as the Seven Crests. The Authority typically stays in the background and resides in what is known as the Shroud, the true political seat of power in the land. It is located on an island in the center of the land that is covered by a magical mist from all sides hence its name. The land was originally split into seven territories of equal value based on size, resources, and overall sustainability and self-sufficiency. None of the territories could survive wholly without another. This was done purposefully by the Last Emperor of the Authority before he chose to shift the Authority's focus from overt power to being the invisible hand. This shift occurred when the Brokers began to amass more power and influence. The Crests knew where the true power lied as even the most ambitious and/or arrogant Royal Kotada of the Crests dared not challenge the Authority. The understanding is clear, the Crests have the amount of power that they have because the Authority gave it to them and the Authority can focus on their secret cold war with the Brokers because the Crests are ruling the territories. The Brokers actually need the Crests in power as well since ambitious Kotada Nobles and common Kotada are their primary clients. So as long as the Crests are in power and able to battle each other for position, there will be those seeking to gain an advantage through any and all means available.

In the case of disputes between the Factions, the Authority remains neutral except in extreme situations where one faction is amassing too many powerful Kotada. In situations where the Authority has to step in, the consequences are often swift and dire. Their control goes unquestioned because of this. So to be summoned to the Shroud outside of scheduled meetings and official business is a dreaded experience for even the ruling royals of both human and Kotada houses as it is a grave transgression to distract the Authority from what it does focus on, which is monitoring and policing the flow of Spirits and their powers. Among the Tyrael and Kotada are a sort of boogeyman that parents tell their children to keep them behaving and as far as humans are concerned, they know that there is a force within the Kotada society that keeps them in line, but for the most part they believe it to just be part of their respective Crest's power structure.

Population Breakdown
Human = 70%
Unbonded Tyrael = 15%
Kotada = 10%
Nobility Class Kotada = 4%
Royal Class Kotada = 1%

Lifespan Comparison
Human Generation = 75-80 years
Tyreal Generation = 225-250 years