Based on

Movies like Sailor Moon SuperS: The Movie - Black Dream Hole (1995)

The wicked Badiyanu has come to capture all Earth's children to gain enough power to absorb the planet in her Black Dream Hole. The Black Dream Hole is in Badiyanu's castle and absorbs the dream energy from children. The more children Badiyanu kidnaps, the larger the dream hole gets. The Sailor Team must save Earth's children and prevent the Black Dream Hole from enveloping the entire planet!