The "Sailor Power Guardians" (守護力精霊 "spirits with protective powers") were spirit-like beings who looked similar to their respective Sailor Guardians. The Guardians seemed to dwell within the palaces of the Sailor Senshi.
In the manga only, the Sailor Power Guardians look like sprites — tiny versions of the Inner and Outer Sailor Senshi who live in their respective castles. The series shows only the Inner and Outer Sailor Senshi as having Power Guardians, and although all eight are shown, only three of them are referred to by name: Guardian Uranus, Guardian Neptune, and Guardian Pluto. The rest of their names appear in cast drawing in one of the art books. The Sailor Power Guardians are responsible for keeping the castles safe while the Sailor Senshi are on Earth, and provide some of the Sailor Senshi with their Sailor Crystals during the Dream arc.
Each Power Guardian communicates with her respective Senshi by calling on the power of that one's own Sailor Crystal. The Power Guardians can help the Sailor Princesses call on the energy and power of their own Castles to produce a new transformation-their evolved Super Sailor forms. Thus they upgraded to their Super Sailor forms and poured these much stronger and more powerful abilities into the Rainbow Moon Chalice, which in turn allowed Usagi to evolve into Eternal Sailor Moon for the first time.
The Sailor Power Guardians disappear in the Stars arc around the time of the murders of the Sai;pr Senshi they protect. The exact nature of their fate remains unclear, although the Sailor Senshi themselves later undergo rebirth.
They appeared for the first time in Act 41 when the Eternal Sailor Senshi asked for the power of their palaces to help Eternal Sailor Moon defeat Queen Nehellenia, and a second time in Act 45 when Super Sailor Pluto had arrived at her castle.
List of Guardians
- Guardian Mercury
- Guardian Mars
- Guardian Jupiter
- Guardian Venus
- Guardian Pluto
- Guardian Uranus
- Guardian Neptune
- Guardian Saturn
- It is rumored that Diana the Moon Fairy was originally meant to be Eternal Sailor's Moon's power guardian.