Queen Metaria is a malevolent, shapeless energy entity, akin to the impersonal Japanese evil deity Amatsu-Mikaboshi. Originating from solar radioactivity, she is the mastermind behind the Dark Kingdom and an incarnation of Chaos, the ultimate villain in the Sailor Moon manga. Her name is sometimes spelled as Metallia, but the author's preferred spelling, Metaria, appears in later manga editions. In the anime, she is known as Metalia.
In the manga, when Prince Endymion and Princess Serenity were about to marry, Metaria exploited those on Earth who opposed their union, including Beryl, whose feelings for Endymion were manipulated by Metaria. Following a war, Metaria was sealed at the North Pole and placed in suspended animation.
In the 20th century, Metaria revived Beryl and commanded her to find the Silver Crystal to free herself. After capturing Endymion's reincarnated form, Metaria possessed him to use as a host, leading to Beryl's demise in battle. Sailor Moon eventually kills Endymion, freeing Metaria, who is ultimately destroyed by Sailor Moon.
In the anime, Metaria follows a similar path with some differences. She becomes powerful enough to resurrect independently and possesses the dying Beryl, transforming into a towering goddess-like figure.
In the English dub of the anime, Metaria is referred to as the Negaforce, a blend of "Negative" and "Force." This dark lord or lady is a god-like being to the inhabitants of the Negaverse. Though supreme in its dimension, it does not answer to any beings from the human realm, including Chaos. Unlike Metaria, the Negaforce never seems to have been sealed away and has always been a faceless diabolic force, content to let Beryl handle the actual work.
