Petz, known as Prizma in the English versions, is the eldest of the four sisters and possesses the magical power called "Dark Thunder" in the anime. In the manga, she is depicted using a tornado, similar to Sailor Jupiter's Flower Hurricane. She is named after the mineral petzite and serves as the counterpart to Makoto Kino.
In the manga, Petz is assigned "Code003 Operation Re-new," during which she and her UFO release viruses onto Tokyo. Makoto becomes infected and collapses in her apartment. Upon awakening, she finds herself being choked by her doppelgänger and transforms into Sailor Jupiter to fight it, revealing it to be a droid. Petz arrives in her UFO, amused that Jupiter is still alive, then vows vengeance for her two deceased sisters. She traps Jupiter in a tornado summoned with the Black Crystal. While watching Jupiter, she fails to notice the arrival of Sailor Moon and Sailor Venus, and is killed by Moon Princess Halation. However, Rubeus manages to kidnap Jupiter.
In the anime, Petz frequently clashes with Calaveras, but they often end up working together. She is very proud and willing to step on others for personal glory and power. She also harbors bitterness over a past relationship and reacts strongly when teased about it by Calaveras. After Cooan and Berthier betray them, Rubeus gives Petz a stick that infinitely increases her dark powers and instructs her to use it to kill both the Sailor Senshi and her fallen sisters. He warns her that failure means she won't be allowed to return. The stick dramatically boosts Petz's powers and corrupts her personality, allowing her to gain the upper hand against the Sailor Senshi. She turns on Calaveras, attempting to kill her along with the other two sisters. However, the Senshi regain control, knock the stick away, and reduce her power. Rubeus then reveals he expected Petz to fail; his true goal was to lure the Sailor Senshi out and sacrifice all four sisters to destroy them. He activates the stick's true power, creating a massive time-vacuum. No longer possessed and feeling remorseful, Petz decides to destroy the stick by jumping into the vortex. Her sisters stop her, and the Sailor Senshi ultimately destroy the vortex, purifying Petz and Calaveras.
Later, Petz and her sisters find a wounded Saphir. Despite initially thinking he came to punish her sisters, Petz tends to him. It is revealed that Petz and Saphir were romantically involved, explaining her bitterness towards men. After Saphir is killed by Wiseman, Petz senses his death and is heartbroken but remembers his smile for her.
