| 1 | Murderbot |
| The main protagonist, a SecUnit with hacked governor module. Aka: Murderbot |
| | Dr. |
Volescu | A scientist on the PreservationAux survey team. |
| | Dr. |
Bharadwaj | A scientist on the PreservationAux survey team. |
| | Dr. |
Mensah | The leader of the PreservationAux survey team. |
| | Dr. |
Pin-Lee | A scientist specializing in legal and policy matters. |
| | Dr. |
Arada | A biology specialist on the PreservationAux team. |
| | Overse |
| A certified field medic on the PreservationAux survey team. |
| | Dr. |
Ratthi | A biologist working with the PreservationAux team. |
| | Dr. |
Gurathin | A reserved scientist on the PreservationAux survey team. |
| | HubSystem |
| An advanced central artificial intelligence that manages a habitat or station. |
| | MedSystem |
| The governor module, a software system that controls SecUnits. |
| | DeltFall |
| A non-corporate exploratory survey team operating on the same planet as PreservationAux. |
| 2 | PreservationAux |
| A scientific research group, part of the independent Preservation Alliance. |
| | SecUnits |
| Cyborg constructs of cloned human material and robotics used for security. |
| 4 | Human Bot Units |
| Cyborg constructs serving as security agents. |
| 6 | GrayCris |
| A ruthless corporation involved in illegal alien artifact mining and terraforming. |
| | Blue |
| The leader of the GrayCris group. |
| | Yellow |
| A member of the GrayCris group. |
| | Green |
| A member of the GrayCris group. |
