Zoicite is credited for having eliminated the "traitorous" Nephlite and assumes his command, but Queen Beryl changes the mission.
Instead of gathering energy, Zoicite is to secure seven crystals. They are the Rainbow Crystals, the seven fragments of the shattered Imperium Silver Crystal, the most powerful crystal in the universe and the only object truly powerful enough to stop even Beryl.
As she releases the crystals from the people of Earth, who unknowingly carry them, the seven Shadows, Queen Beryl's finest warriors, are released from the crystals and take over the people's bodies. However, Zoicite's threat is matched in kind, thanks to the arrival of Sailor Jupiter and the healing power of Sailor Moon's Crescent Moon Wand.
Zoicite teleports in and out in a shower of flower petals, and she can also use these petals to trap or distract her opposition. She was trained by the most senior of the warriors, Malachite, and the two have a long-standing relationship that goes beyond a student's respect for her teacher. Malachite's always there when she needs help or a word of comfort.
But not even Malachite can help her with her greatest weakness: her lust for revenge. Over the course of her mission, Tuxedo Mask has always shown up to try to spoil things, and she eventually becomes enraged. She becomes so enraged that she disobeys the direct orders of Queen Beryl. Instead of taking Darein (whom they now know is Tuxedo Mask) alive, she plots twice to destroy him. She almost succeeds the second time, but in the process, Sailor Moon's true past as Princess Serena as well as cause the Imperium Silver Crystal to be reformed and secured in the Princess' possesion.
Of course, Queen Beryl gets very ticked off, and she excecutes Zoicite for insubordination.
