The 11th episode of the anime Sailor Moon features a fan-favorite monster: Murido.
Murido: The Nightmare in Dream Land | Of Moon and Monsters
Kigan and Sailor Mars | Of Moon and Monsters
The tenth Sailor Moon episode introduces Sailor Mars as well as Kigan, a monster who didn't appear in the manga.
Ramua: The Controller of Time | Of Moon and Monsters
In the ninth episode, Sailor Moon and Sailor Mercury battle the time-manipulating Yōma called Ramua.
Garoben and Sailor Mercury | Of Moon and Monsters
The eighth episode of Sailor Moon brought on Sailor Mercury to help defeat the teacher from hell, Garoben.
Derella: The Glass Monster | Of Moon and Monsters
In the seventh episode, Sailor Moon encounters the glass Yōma Derella after preparing for the Cinderella Caravan.
Tales from the Paulside 