In the Star Control games, this is the name of the species that served the Green Ur-Quan, the Kzer-Za. In the original game the hierarchy is composed of (in order of "rank") :

  • Ur-Quan
  • Mycon
  • Spathi
  • Androsynth
  • VUX
  • Ilwrath
  • Umgah

After the first game, the player can learn that the Thraddash was formally part of the hierarchy, but considered so weak by the Ur-Quan they decided to keep them away from the frontline, thus explaining that they don't appear in Star Control I. With the defeat of the Alliance of Free Stars the Yehat are the only alliance race to choose to join the battle thralls, the other races all choose to become fallow slaves instead. The exceptions to this are the Shofixti who instead chose to launch one last kamikaze attack on the Ur-Quan all but destroying themselves in the process and the Ariloulaleelay who return into their home dimension. Shortly before the start of Star Control 2 the Androsynth leave the hierarchy when they disappear from the face of the universe, their area of space becoming inhabited by the Orz.