Yaderan

The Yaderans are a space-faring humanoid species native to the Gamma Quadrant planet of Yadera Prime. They possess highly advanced hologram-generating technology.

In 2340, the Yaderan's homeworld was conquered by the Dominion. One of the survivors, Rurigan, left to a desert colony on a nearby planet. He created a holographic village for him to live and holographic versions of his friends and relatives. Rurigan has never revealed the truth to them. Thirty years later, a problem with the machine caused some of the holograms to vanish, which eventually lead to the villagers discovering about their true nature. The hologenerator was fixed with the help of Dax and Odo, and the missing villagers were brought back. They now know that they are holograms, but they are still not aware that Rurigan is not, leaving them to wonder about who could have created them, and why.