WARNING: The following contains spoilers for Sailor Moon Eternal: The Movie, now available on Netflix.
Throughout Sailor Moon, Usagi dramatically grows in power, going from a schoolgirl to something close to a cosmic god. And the second part of Sailor Moon Eternal gives viewers the chance to witness Sailor Moon transform into the fittingly named Eternal Sailor Moon. In the eyes of many fans, Eternal Sailor Moon is Sailor Moon's "final form," but how does it come about, and how much power does Eternal Sailor Moon wield?
In Sailor Moon Eternal, Usagi turns into Eternal Sailor Moon through a multi-step process. After getting beaten down by Nehellenia and having the Silver Crystal stolen, Usagi and Tuxedo Mask embrace, and this kiss breaks Nehellenia's darkness and returns the Silver Crystal to Sailor Moon. Sailor Moon then enters her Super Sailor Moon form and produces the Holy Grail. The other Sailor Scouts turn into their princess forms and send their energy to Sailor Moon's Holy Grail, turning it into the Holy Moon Chalice. Then, using the power of the Holy Moon Chalice, Sailor Moon can enter her Eternal Sailor Moon form.
Now in Eternal Form, Sailor Moon produces the Eternal Tiare, a new weapon that takes the form of a white staff with a crystal on the one end. Sailor Moon emplores her friends and the Silver Crystal to send their power to the Eternal Tiare. With a shout of "Silver Moon Crystal Power!" Sailor Moon produces the Silver Crystal and gives it a new form that resembles a blooming flower.
The other Scouts send their power, and Tuxedo Mask reaches inside himself to discover the Golden Crystal and contributes its energy to the fight. Now fully charged, Eternal Sailor Moon can use her "Starlight Honeymoon Therapy Kiss" attack, charging at Nehellenia and striking her mirror with a massive wave of energy. This single strike not only shatters the mirror but also destroys Nehellenia, turning her to dust while freeing Helios and removing the dark moon from the sky, showing the incalculable strength of this attack.
In Sailor Moon Eternal, it is said that Eternal Sailor Moon has powers close to those held by Queen Serenity. Which, considering Queen Serenity's immense power, is quite impressive. On paper, Sailor Moon's Eternal form is the combined power of all of the Sailor Scouts wrapped together, so it is a massive boost to her usual abilities. The fact that one fully charged hit was enough to vaporize Nehellenia, someone who had comfortably dealt with the Scouts up until that moment shows that Eternal Sailor Moon isn't someone to be trifled with.
However, Eternal Sailor Moon does get more powerful in the manga and original anime. In the manga, Usagi learns to unleash an even more powerful attack called "Silver Moon Crystal Eternal Power," which she uses to defeat Chaos, a being that easily outclasses Nehellenia. The original anime also showed that Eternal Sailor Moon can get stronger via an attack called "Silver Moon Crystal Power Kiss." This attack uses the Moon Power Tiare, an improved version of the Eternal Tiare that has the Holy Moon Chalice attached to it.
And, of course, Neo-Queen Serenity has powers that are way beyond the ones possessed by Eternal Sailor Moon. Neo-Queen Serenity's mastery of her powers allows her to resurrect massive groups of people and project herself through time and space. She was able to control the Silver Crystal in the past and future, putting her on another level from Eternal Sailor Moon.
Sailor Moon Eternal gives us a brief taste of Eternal Sailor Moon's powers. And, while she is strong, Usagi can get even more powerful. And she will need to if she wishes to deal with the other, more dangerous threats that lurk in the shadows, waiting for their moment. However, even with only a fraction of Queen Serenity's power, Usagi is still one of the most powerful beings on Earth, easily outclassing most of her older foes and every other person she hangs out with.
