Queen Nehellenia, The beautiful leader of the Dead Moon, she turns to evil when she realizes she can never stay young and
beautiful forever. Long ago, she and her powers were sealed into a mirror by Queen Serenity. I don't know why people refer
to her as Nehellenia when apparently she was a Queen herself.
The Story Behind Queen Nehellenia's becoming of darkness: In the manga, Queen Serenity's role is slightly larger: instead
of appearing as a sprite to the Senshi, there is a holographic image (though she looks exactly the same). She also appears
after Usagi defeats Queen Metallia and asks her to take her place as Queen of the Moon (but Usagi refuses). The story becomes
more interesting in the Super S manga, where Usagi has a series of flashbacks to when she was a child in the Moon Kingdom.
It is revealed that the evil Queen Nehellenia was the sister of Queen Serenity, and that both originally came from somewhere
else in the galaxy before they arrived at the Moon. When Princess Serenity was born, Nehellenia tried to convince Queen Serenity
to join her in her evil plans. When Serenity refused, Nehellenia put a curse on the baby Princess and tried to claim her victory,
but was soon defeated when Queen Serenity sealed her in a mirror.
When the princess had reached four or five years old, she started having nightmares, predicting the outcome of her curse.
It is here that Queen Serenity gives Usagi the most important piece of advice that she ever receives in the entire series:
"We all have a star in our heart. Darkness and light are always right next to each other. Show a little fear or a drop
of tear and the darkness will grow and start to attack, consuming the light. Serenity, you must always keep the star in your
heart shining strong to defeat the dark and evil souls. That is your most important mission, Serenity..."