Shadow Galactica is the empire built by Sailor Galaxia. Its mission was to collect Sailor Crystals.
In the anime, when Sailor Galaxia destroyed a planet, there was a possibility that she would offer the Senshi of that planet a chance to live after she took away her Star Seed , as well as increase her power, by the use of special golden bracelets. In return for this augmentation, the Senshi would usually end up losing her free will, and would work for Galaxia until her death. Usually, the method of death for a worker of Shadow Galactica in the anime was for the displeased Galaxia to simply remove the worker's bracelets, thus causing them to disappear.
When she arrived on Earth, the four Sailor Animamates were with her, and they set up shop as Ginga TV and masqueraded as talent agents to find The True Star Seeds. However, they ended up only with Phages and all but Sailor Lead Crow died as a result of having their bracelets removed.
As was implied in the anime, there were real Sailor Senshi, such as Sailor Lethe and Sailor Mnemosyne, who worked for Galaxia in hopes of making a better future for themselves - a future they believe Sailor Moon could not offer them.
However, most of Galaxia's followers were not real Senshi. They were normal people who had killed their planet's Senshi and given the Sailor Crystals to Galaxia. These people were given the golden bracelets as a reward, giving them power comparable to that of a Senshi, with the additional promise of a real Sailor Crystal once Sailor Moon was defeated. However, most of them totally lost their free will in the process and forgot Galaxia's promise, perhaps ensuring that they would not interfere with Galaxia's true plans to recreate the universe. The bulk of this group included the Sailor Animamates and Sailor Phi and Sailor Chi, though the latter two seemed to have a great deal more free will than the Animamates.
Unlike in the anime, where only Galaxia managed to kill any Senshi, in the manga the subordinates had much better luck in their mission. On Earth, Aluminum Seiren killed Sailor Mercury and Sailor Jupiter, while Lead Crow killed Phobos and Deimos. Tin Nyanko managed to injure Luna, Artemis, and Diana, and cause them to lose their speaking ability, while Sailor Lethe finished them off. Sailor Phi and Sailor Chi both killed the Sailor Starlights, and Sailor Chi killed Sailor Kakyuu. Sailor Galaxia's stronghold inside Shadow Galactica was the castle called Galaxia Palace.
- Sailor Iron Mouse
- Sailor Aluminum Siren
- Sailor Lead Crow
- Sailor Tin Nyanko
- Sailor Heavy Metal Papillion - manga only
The True Sailor Senshi
- Sailor Lethe - manga only
- Sailor Mnemosyne - manga only
The Guardian Senshi - Involuntarily in the manga
- Sailor Uranus - Voluntarily in the anime, involuntarily in the manga
- Sailor Neptune - Voluntarily in the anime, involuntarily in the manga
- Sailor Pluto - Involuntarily in the manga
- Sailor Saturn - Involuntarily in the manga