And this warrior was Sailor Galaxia. Since that time, she has slowly been corrupted by Chaos, and launched a war against the entire galaxy, a war she is steadily winning. Her desire is to possess all the True Star Seeds... the pure spirits of planets and stars, which incarnate into the Sailor Senshi of that celestial body. While her ultimate aim is unknown, this goal is terrible enough. Stripped of their Star Seeds, the planets where Galaxia conquers are left as lifeless husks. Doing this often involves the obliteration of whatever Senshi protected that celestial body, of course, but not always - some Senshi, in despair or rage or even a secret hope of betraying Galaxia, give in to the conqueror. Galaxia humours these traitors, allowing them to keep their lives even after she removes their Star Seeds. She does this by means of bracelets she can create, similar to those she wears, that allows her minions to live without their souls (even as Galaxia herself does, a fact she does not share with her minions).
Little is known about Galaxia's personality before she became corrupted by Chaos, save that she was an incredibly independant warrior who took the burdens of the galaxy on her shoulders. This aspect has not changed. Galaxia is utterly self-reliant. Though she suffers her minions, she does not rely on them, and will eradicate even loyal allies without hesitation if they no longer serve her purposes. When she marches to battle, she is at the forefront; she needs neither ally nor shield. She delights, however, in turning her enemies against each other, and enjoys the spectacle of once-loyal friends now fighting amongst themselves. This too only proves to her that reliance on others is a fool's ideal. Galaxia dismisses the morality of her actions with a simple application of fiat: she owns the majority of the galaxy, and as its ruler, only she may decide what is right and wrong. While questioning of her authority and defiance of her power often amuses Galaxia, that amusement can turn to deadly retribution with very little notice. There is virtually no empathy or sympathy for life left within her: Galaxia can and has wiped out the entire population of millions of planets without the slightest hesitation or regret.
In sheer power, Sailor Galaxia is not only the most powerful Sailor Senshi that has ever lived, but one of the most powerful beings imaginable. She can teleport across the galaxy is an eyeblink, and can launch energy blasts of surpassing power, as well as rip out the Star Seeds of any being that possesses one (True or otherwise) with a single blast. She may also summon a storm of black lightning, the strokes of which will eradicate buildings and strip the Star Seeds from anyone struck; this lightning can "cleanse" an entire city in a horrifyingly short time. Were that not enough, she can also summon a corrupted version of the same Sword of Sealing she used to defeat Chaos to use as a weapon. So skilled, fast, and powerful is she that regular Sailor Senshi are as nothing but gnats to Galaxia: she was capable of killing the entire cadre of inner Senshi in literally seconds, and the Outer Senshi in barely more time. Her defence is no less potent than her offence: as well as shrugging off the attacks of the likes of Sailor Pluto, she rather contemptuously overpowered or ignored even the most powerful attacks Sailor Moon was capable of.