Kzer-Za • Kohr-Ah
| Sentient Milieu|
|Kzer-Za • Kohr-Ah|
| Path of Now and Forever|
Ur-Quan Hierarchy • Battle Thrall • Fallow Slave • Oath of Fealty Doctrinal Conflict
|Dreadnought • Marauder • Sa-Matra|
|Excruciator • Slave Shield • Talking Pet|
The Battle Thralls of the Ur-Quan Hierarchy are the species who have pledged to serve the Ur-Quan Kzer-Za by helping them enslave other sentient races. Their duties include providing military support for the Kzer-Za and watching over slave-shielded worlds while their masters pursue more important matters. It is unknown if Battle Thrall status is permanent or if the adoption of a program of Battle Thralls has only been instituted by the Kzer-Za to help put down local conflicts, such as the local wars with the Alliance of Free Stars, and are afterwards slave-shielded. Certainly it seems unlikely that the Kzer-Za fleet has simply left whole civilizations of Battle Thralls free to operate their own affairs indefinitely before moving on to others, given their actions within our own region of space, but the details of administration of the Hierarchy outside of our local wars are unknown.
Battle Thralls have rights to travel through space and to retain some autonomy on their homeworlds, but are not allowed to commit acts of violence against other law-abiding Battle Thralls or Fallow Slaves. If the Kzer-Za judge a particular already-present government to be properly constituted and legitimate, they appear to allow it to continue operating, as was done with the Yehat Veep-Neep Dynasty. In other cases they have been known to forcibly dismantle governments that appear intractable in their violations of the Ur-Quan slave laws and install new ones, such as their intervention in establishing the Thraddash Culture 19 following the end of Culture 18.
 Hierarchy Battle Thralls during the Ur-Quan Slave War (Star Control I):
- Mycon - only known race to actively seek out the Ur-Quan and request Battle Thrall status.
- Spathi - intended to become a fallow species, but were tricked by the Umgah into becoming thralls.
- Thraddash - did not directly participate in the Ur-Quan Slave War.1
 Hierarchy Battle Thralls at the beginning of Star Control II:
- Yehat - the only former Alliance member to choose Battle Thrall status, the Hierarchy Veep-Neep government can later be overthrown by pro-New-Alliance Starship Clan Revolutionaries.
- Spathi - can defect to the New Alliance of Free Stars, then will soon after encase their homeworld in a slave shield.
- Thraddash - the Hierarchy's Culture 19 government can later be overthrown by pro-New-Alliance Culture 20 government.
- Umgah - eventually enslaved by the neo-Dnyarri, but revert to Battle Thrall status once freed.