Dark Kingdom
After continually thwarting the Dark Kingdom and defeating several of its generals, Usagi awakens as the moon princess — Princess Serenity — and acquires the Silver Crystal. However, Mamoru is captured by the Dark Kingdom and brainwashed to work for them. The Sailor Soldiers learn of their past lives on Silver Millennium, an ancient kingdom on the moon. The Sailor Soldiers served as Serenity's friends and bodyguards, and Serenity was in love with a prince from Earth named Endymion (Mamoru's past identity). However, the Dark Kingdom attacked and destroyed Silver Millennium, resulting in the deaths of Serenity, Endymion, and the Sailor Soldiers. Serenity's mother — Queen Serenity — used the power of the Silver Crystal to vanquish Queen Metaria and end the war. She also used the crystal to send the fallen into the future to be reborn on Earth, hoping to give them a second chance at peace.