Pharaoh 90
Master Pharaoh 90 (師・ファラオ90, Masutā Farao 90?) is a malevolent alien from “Tau Ceti Star System;” further details on its origins are unknown. It appears only as a huge black sphere with tentacles.
In the manga, Pharaoh 90’s goal is to merge itself with the planet Earth and make it his home. In the anime, it wants simply to destroy it by bringing about the Silence. Pharaoh 90 is the one who provided the daimon egg of Mistress 9 to Professor Tomoe, taking advantage of Tomoe’s desire to save his daughter. In reality, Pharaoh 90 simply needed to provide a body for Mistress 9 so that she, in turn, could open a portal for Pharaoh 90. Pharaoh 90 was destroyed by Sailor Moon and Sailor Saturn in the anime, but in the manga, it is simply driven back to Tau Ceti by Saturn and then sealed away forever by Sailor Pluto.
Like all of the head villains in the manga, Pharaoh 90 is later revealed to be an incarnation of Chaos, the ultimate enemy of the series.