Queen Metallia
Queen Metallia is the ruler of the Dark Kingdom. She has the form of blood. When Metallia speaks liquid black waves of darkness represent her sound waves when she talks to Queen Beryl. She gave the power to turn Prince Endymion to the dark side, and go against the sailor senshi.
She gave Queen Beryl the energy to defeat Sailormoon, and Queen Beryl became Queen Metallia. Of course it wasn't enough power to destroy Sailormoon, cause we all saw her and the rest of the Inner Senshi kick Queen Metallia's butt. She was then moon dust, from then on.