Phase World sits at the centre of the oldest of the Three Galaxies, fifth planet of an aging red giant and a nexus of interdimensional trade. It is a Class M planet approximately the size of Earth. It has a rotational period of 22.3 hours, and an orbital period of 53 years. It has little axial tilt and an artificially uniform climate with a temperature range of 21° to 27°C over the entire planet. Gravity is close to 1G, and the atmosphere is 20% oxygen, 78% nitrogen and 2% other gasses. Phase World is ruled by the Prometheans, a powerful race of humanoid aliens who make up 71% of its 5 billion inhabitants. 10% of the population are Draconids and 4% are so-called Phantoms. The remaining 15% comprise the citizens of and visitors to Centre.

Phase World is an incredible transdimensional city that is also a space port located at the edge of three galaxies. This means that visitors come not only from other dimensions but from the neighboring galaxies as well. Consequently, Phase World is one of the more unique ports in the Megaverse where one can engage in cosmic adventure, space exploration, smuggling, bounty hunting and more.

Centre is the largest city on Phase World in the Corkscrew, largest of the Three Galaxies, with a population of over six hundred million beings. The city is a single structure—from the air, it looks like a huge truncated pyramid over a kilometre and a half high. The structure reaches at least as far underground. It is surrounded by a complex of shuttle and ship landing pads, and the entire upper surface is parkland.

The master race of Phase World, Promethians are a humanoid species ranging from 2 to 3 metres in height, with barrel chests, thick limbs and round heads. They are hairless with beady jet-black eyes and have no apparent nasal apparatus. They do not breathe except to speak, and can survive extended periods in vacuum. They can also survive most environmental hazards, such as radiation exposure and toxic fumes. They are immensely strong and their purplish, rock-hard skin resists most physical damage. Prometheans are extremely long-lived. It is believed that the Prometheans normally encountered are immature specimens an that the adults (known as "second stage Prometheans") are much larger and more powerful.

Prometheans can be encountered in any walk of life, and are very much like Humans in personality. They are highly psionic, with a wide range of abilities.

Draconids, despite their reptilian appearance, more closely resemble mammals in their physical makeup. They are roughly human-sized, with long reptilian snouts, bat-wing shaped ears and short tails. Their scales range in colour through red, green and blue.

Draconids work closely with their Promethean overlords, virtually running the planet for them, acting as administrators and guardians. Most, if not all, Draconids are psionic.

"Phantoms" are an energy race, able to take on corporeal form. Their normal form is a geometrical configuration of coloured lights. They can take on pretty much any shape, but generally affect humanoid form. They can maintain their physical bodies indefinitely, but lose many of their powers while in a body. It takes a Phantom 1 to 4 hours of intense concentration, but only a few seconds to disperse it. Although they are not psionic, in their energy forms they have abilities which emulate many psionic powers.

Humans and their humanoid brethren in Centre are much the same as in the PCs' home universe and most other alternate universes.

Catyr are tall, statuesque humanoids with red skin and golden or bronze-coloured hair. Their homeworld, Catyr-Ra, has a high level of radioactive heavy metals - so much so that Catyr themselves are mildly radioactive. Catyr are culturally and temperamentally similar to Humans. Some scientists believe that Catyr are genetically altered Human stock transplanted by an ancient race, perhaps by the Preservers. Many Catyr believe the opposite to be the case.

Noro are tall, thin, spindly humanoids, with oversized black eyes and long slender fingers. Their mouths and lower jaws are narrow in relation to the rest of their head, but not grotesquely so. They have six fingers on their hands and six toes on their feet. Instead of hair, their heads sport bony spikes of varying length that grow tike hair. Some Noro affect a mohawk-like crest of spikes, while others "shave" them all off. In human terms, some Noro can be very attractive, albeit outlandish. The race favors tunics or togas for ceremonial occasions and jumpsuits or bodysuits otherwise.

Early in their space-faring history, the Noro caused the nuclear annihilation of a neighbouring world. Realising their greivous error, the species as a whole has adopted a pacifist philosophy.

Seljuk are large reptilian bipeds ranging from 2.5 to 3.5 metres in height and massing from 275 to 450kg. They resemble humanoid versions of Earth's Tyranosaurus Rex, with long tails and digitigrade lower limbs, but with upper limbs proportionate to their size. The word that best describes the Seljuk culture is "chivalric" - they value honour and courage above all else.

The Uteni are a tall (2.5m), hairless humanoid species with a very slender build and pale blue skin. They have large eyes and no mouth or nose. They are capable of altering their build and features to resemble any biped from 1.25 to 2.75m in height, though their colouring always remains the same hue, and they cannot simulate hair.

Uteni are moderately psionic, and have the moral attitudes of Ferengi, although with more conventional manners and a greater grasp of subtlety. Naruni Enterprises, a major commercial venture in the city, is fronted by the Uteni.

Wolfen are large caninoid bipeds, unrelated to but resembling the much smaller Vargr. Unlike the Vargr, Wolfen are rigidly organised, with a strong central government resembling that of the ancient Roman Empire on Earth, or the modern Romulan Star Empire. The Wolfen code of honour includes an innate sense of superiority to other species and a belief in the destiny of the Wolfen race to rule the Galaxy. The Wolfen Space Empire is not currently hostile to the Federation, and did not take part in the recent Dominion War.