"Adaptability, Order, Innovation"
The Chiss are a species, but they do not have to be. The Mandalorians believe that any species may become a Mandalorian, yet they are not the only ones with such an ideology. House Theyiri believe that any species may become Chiss, but first, they must neglect their people, culture, and any religion they may have and instead swear loyalty to the Chiss Ascendancy, and to House Theyiri secondarily.
Adaptability is key to the survival of the Chiss culture, House Theyiri is open to much that before Chiss had never accepted so eagerly. By viewing other peoples, House Theyiri can take their best traits and absorb them into the Chiss culture should it be needed. This shows in ways such as Brae'owiawo'theyiri, the head of House Theyiri, owning two companies, and interacting more frequently with non-chiss species.
Order has kept the Chiss alive, through countless atrocities, wars, plagues, and other disasters. All members of house Theyiri must swear their loyalty to the Chiss Ascendancy first, and to House Theyiri second. They must obey every command from their superiors, and all that they do must further the Chiss Ascendancy.
A clear Hierarchy is seen in the Ascendancy and within Theyiri as well. A single ruler of the house controls commanders who then control grunts. Without order and this clear hierarchy of command then Csilla, and other Chiss worlds would fall into anarchy.
Technology is the key to galactic dominance, and none understand this more than the Chiss. Theyiri explores technological options from around the galaxy, from having access to Clone Labs on Kamino, to APEX Technologies producing ships, weapons, and armor, and constantly trying to find new ways of improving their tech which has given their tech wonders such as Duraweave.
House Theyiri is welcoming any scientist willing to swear loyalty to the Ascendancy, and will provide funds, labs, and test subjects to those willing to cooperate. Together, we will drive the Ascendancy into the future and into its rightful place within the galaxy.