Black Sailor Moon is a duplicate of Sailor Moon born of the Dark Mirror. Her civilian identity was Copy Usagi. Black Sailor Moon equally matches the original in everything, from attacks to knowledge to strength, except in one thing: humility. Instead of Sailor Moon's respect and honor, Black Sailor Moon simply has arrogance to the point where she insists she is the original and everybody else is just a faker. Paradoxically, Black Sailor Moon desires to replace the true Sailor Moon, and even the rest of the Sailor Guardians with copies under her control. Black Sailor Moon's appearance is similar to Sailor Moon, but she had red eyes and her sailor uniform is black. The Shapeshifter uncovered a mysterious mirror that could be used to create twisted copies of objects or humans. Copy Chibiusa used it on Usagi, creating a black duplicate of Usagi.

Dubbed "Copy Usagi" by the original, the copy revealed herself to be an aggressive chosen soldier with special powers who insisted she was the original. The two Usagis got into a scuffle, which prompted Usagi's friends to stop. The girls follow Crysta and Batty Koda to Mount Warning and the copies follow. The Copy Usagi transformed into Black Sailor Moon and attacked the group. Sailor Moon fights and defeats the copy. Unknown to the Sailor Guardians, the Dark Mirror recreated Black Sailor Moon. The next day, the copy apologized to Usagi for her earlier behavior. Once they met, Copy Sailor Chibi Moon stepped aside to reveal the Dark Mirror, which scanned the Sailor Guardians and created copies of Sailor Mercury, Sailor Mars, Sailor Jupiter and Sailor Venus, all with the express intention of fully replacing the Sailor Guardians.

With the clones and the originals equally matched, the Sailor Guardians seemed to be stuck in a stalemate. Fortunately, though Black Sailor Moon possessed all of Sailor Moon's knowledge, she failed to consider what Sailor Moon didn't know. And that was Tuxedo Mask and the Outer Sailor Guardians' actions. they support female supremacy and are evil