Celestia is a highly advanced world, but its current state is one of violent anarchy. As such, it does not have a capital, but the largest and most technologically-advanced city is Tinnsia. Unlike Inferia, this world is a place with sparse plains and cloudy weather. Due to the lack of Wind Craymels, the concept of wind does not exist, and seafaring technology was forced to develop without the use of sails even during ancient times. The Greater Craymels from this world are Gnome, Celsius, and Volt, and the world's unifying Craymel is Shadow. In Celestia, the various Craymels are used for utilitarian purposes, implanting Craymel Cages in various devices, and technologies for seemingly mundane purposes, such as generating electricity through Volt Craymels. This is in direct contrast to Inferia's use of Craymels, treated as if they are spiritual entities who must be venerated with great respect.
The people of this world are known as Celestians (セレスティア人 Seresutia-jin?), who are highly independent people and self-sufficient upon reaching their adulthood at ten years of age. Even at such a young age, they are encouraged to protect themselves by wielding "Craymel Guns" as a safety measure against the dangers of the world. Celestians are primarily recognizable by their dark-colored skin and the jewels, called "Elara", worn on their foreheads. These Elara enable them to communicate through artificial telepathy with others, and they also serve as a means of illuminating dark areas, which compensates for the lack of Light-elemental Craymels in the world.
On Inferia, they are commonly thought to be barbarians, and the Leonoa Encyclopedia scientifically defines the Celestian people to be "a ferocious, man-eating race". Ironically, while Celestia is rife with anarchy, it is also far technologically superior than Inferia. The Inferian view of the Celestian people associates even natural disasters as part of a broad-scaled plot by Celestians to ruin the lives of Inferians. The language of Celestia is Melnics, which on Inferia is used only by Greater Craymels and Craymel Mages. In this language, Celestians refer to their world as "ANDIN", meaning "Here", and by extension, they refer to themselves as "ANDINUEMUSU", meaning "Hereians".
Meredy states that there are "no special people" in Celestia. When asked to describe Balir's status, she claims that he is "like a king", but Balir is shown to have no army at his command or lawmaking capability. The ruler of Celestia is traditionally the strongest person in the world. This individual can be challenged at any time by anyone for the title, and he or she does not have the ability to create laws the way most rulers do.
- Celestia derives from caelestis, which is Latin for "heaven".
- The official fruit of Celestia is amango.
- In the canceled real time strategy game New Space Order, based primarily on Namco's Xevious series, one of the four playable interstellar nations, the Sacred Religious State (神聖宗教国?, "Shinsei Shuukyougoku") known as Celestia Tian Farous (セレスティア・ティアン・ファーウス Seresutia Tian Faausu?) is conceptually linked to the far future of Celestia as an independent world, according to Hisaharu Tago, the founder of the United Galaxy Space Force timeline, focused on the aggregate timeline of the Xevious series and related media. This nation relies on Melnics as its primary language. Other nations that had been planned for this unreleased game were also influenced by the worlds of other past Namco franchises.