Not much is known about Sailor Galaxia in the anime version, and what little is known is told by her directly. Apparently,
Sailor Galaxia was once the legendary strongest Sailor Soldier in the galaxy. The Sailor Wars pitted all of the Sailor Soldiers
in the galaxy against those who infringed on love and justice. Eventually, the Wars ended when Sailor Galaxia sealed the source
of all malice, Chaos, within her body to save the galaxy. However, Chaos began to increase its power while it was sealed,
and in a last-ditch effort to save her pure heart, Galaxia expelled her Star Seed into the rural galaxy of the Milky Way,
where the newly born stars of love and justice resided.
Now completely controlled by chaos, Sailor Galaxia sought to steal all the star seeds in the galaxy to control it for
herself in the name of Chaos. Among the planets she wrecked was Kinmokusei; the Sailor Soldiers and the Princess of the planet
managed to escape destruction and flee to Earth, the last place that Sailor Galaxia had not invaded.
To be able to enter Earth, Sailor Galaxia needed to do two things first. The first thing was to break the seal of Queen
Nehellenia, in order to force the awakening of the soldier of death Sailor Saturn. Nehellenia inflicted a curse that paralyzed
Mamoru Chiba, which caused the Sailor Soldiers to fight her once more to defend the existence of Sailor Chibi Moon. After
Nehellenia's nightmare was defeated by Sailor Moon, Galaxia began her plan.
The second thing she did was steal the star seed of Earth's guardian, Chiba Mamoru (AKA Tuxedo Kamen). Once this was done,
she sent her Anima-Mates (Sailor Soldiers that were controlled by Galaxia) to find true star seeds belonging to Sailor Soldiers.
After numerous failures, Galaxia would kill the Anima-Mates, until eventually she confronted the Sailor Soldiers herself.
Before the final confrontation between Eternal Sailor Moon and Sailor Galaxia, all of the other Sailor Soldiers' star
seeds were stolen, and the mysterious little girl that had appeared to Usagi Tsukino, Chibi Chibi, was revealed to be an incarnation
of Galaxia's Star Seed. When Eternal Sailor Moon's star seed was stolen, Chibi Chibi loaned her her spirit. Once that was
done, she asked Sailor Moon to kill Galaxia with her weapon, the Sword of Sealing.
Unable to do so, Sailor Moon instead gave Sailor Galaxia the strength to expel Chaos from her body. Once this was done,
Sailor Galaxia's humanity was restored and the star seeds she had stolen were released. Galaxia then left with the task of
returning the star seeds home.