The Bastion was a building constructed by the Stybla family to protect an alien superweapon known as the Starflash around 5000 BBY in the early days of the Chiss Ascendancy, the nation of the Chiss species, in an attempt to never use the weapon. However, centuries later, during a war against an enemy of the Ascendancy, the Chiss were forced to use the Starflash to protect their remaining people from the enemy's fleet. The Bastion was soon after replaced by the Universal Analysis Group (UAG) on the Ascendancy planet Sposia as the guardian of the alien artifacts the Chiss had collected.
Bastion was mentioned in the flashbacks of the 2021 novel Thrawn Ascendancy: Lesser Evil, the final volume of Timothy Zahn's Star Wars: The Ascendancy Trilogy.
Bastion was mentioned in the flashbacks of the 2021 novel Thrawn Ascendancy: Lesser Evil, the final volume of Timothy Zahn's Star Wars: The Ascendancy Trilogy.