The Digital World, known as Digirus by the native Digimon, is very different compared to the Digital World of other timelines. Like how the Digital World normally is, Digirus behaves much the same way with it's inhabitants, from lifeforms made of data, Digimon being able to be created on Computers, and so on. Yet at the same time, however, it exists in the real world and orbits the Jovian planet Neptune, the outermost planet in Sol.
At such a large distance away from the sun, Digirus is unsual for a planet teaming with life like it has. The atmsophere comprises mostly of greenhouse gases inorder for the planet to be a suitable temperature to where humans can easily live. The planet's average temperature is slightly lower than Earth's even then. Oxygen levels are equal to Earth's Carboniferous period, allowing massive Insectoid Digimon to exist on the moon with ease. A day on Digirus is 30 hours long, with a single orbit around Neptune lasting 3 and a half weeks. Even though it exists within the plane of reality now, Digirus can only be traveled to be the use of hi-tech computer based devices or ships. Due to the less gravity, larger Digimon tend to move at full speed compared to when these same Digimon are on Earth. In addition, the lower gravity is the reason Duo reached her 6'07" height, where normally she'd be only 5'06" if the gravity was no different from Earth. Goddreamon, infamously known for it's massive arms and a tiny body, can move normally due to the lower gravity, but still move slower than it normally would since it's home dimension has even less gravity. Due to Fracktamon's seemingly unpredictable attacks, a neighboring dimension was created by Dragoramon so that Fracktamon could be re-located without further harm to anything that neared it's domain.
Digirus's artificial origins can be traced to 5 million years prior to 2011, where an alien race was experimenting with a technology that can make any object on a computer and make an identical version as a real object by beaming it into reality. While it was only experimental at the time, Dragoramon steals some of the technology and uses it to create a moon orbiting Neptune in and bring into the existence the first 8 species of Digimon, and eventually the rest of all Digimon species into existence within the next 5 million years, in which nearly more than a thousand existed by 2011. Humanity at this point was facing a crisis at this point where civilization was on the brink of destruction, all part of Dragoramon's plan to destroy 99% of the human population to move the survivors to Digirus as part of what Dragoramon was ordered to do by The Grand One. It isn't until 2,000 years later when B/C's storyline begins.
Within that timeline the Great Dark Spot on Neptune has reappeared exactly where it was last seen in November 1994.
Sometime before the Aftermath storyline, all humans have been relocated by unknown means to another universe, with no memories of Digirus's existence, while Digirus still exists. The only reason The Grand One keeps the moon around is because certain Digimon cannot exist in the true Digital World in the other universe, because the true Digital World is not within the realm of reality and thus cannot properly process the massive Mechadramon or the powerful Dragoramon.
Digimon World: Bronze and Cobalt Versions
Both Digirus and Neptune have their own locations to explore. Digirus has the more varied locations in the game, having more terrestrial themed Digimon such as Greymon or Bigdramon, where locations within a closer vacinity to Neptune have more extraterrestrial themed Digimon such as Ebemon or Xros Wars Cyberdramon. Depending on weither or not it was chosen to face last, the last of a set of 4 different boss Digimon is found exclusively in Neptune's upper atmosphere, referred to as the Storm of the Gods, referencing the near 2,000 MPH winds in Neptune's atmosphere, typical for a Gas Giant planet. XILA-Mon is the second largest Digimon in the game, second only to Gaiamon, and is faced as it's Mega stage on Neptune if chosen to face last out of 3 others bosses. Storm of the Gods basically consists of a massive area that seemingly goes on forever. Ebemon tends to be found in floating bubble cities within the higher parts of the atmosphere furthest away from the dangerous XILA-Mon. XILA-Mon inhabits the Great Dark Spot region, which is difficult to navigate and and supplies XILA-Mon with the high powered winds that it feeds on. Ebemon's floating bubble colonies tend to be the only places of civilization within the more closer vicinity of Neptune. However, during the main storyline a rogue alien Digimon keeps the Ebemon virtually unseen and renders the colonies unable to be visited due to a massive war going on between the two at that moment. The opposing Digimon race is an alien Digimon much like Ebemon, but are savage war mongers. If XILA-Mon is faced last, you have a chance to encounter them and train easily as they appear quite frequently. They also lead you to XILA-Mon's location, but it is actually a death mission they send you on to keep you out of their business because they don't want any interruptions in their temporary war with the Ebemon colonies. After the main storyline, the Ebemon colonies can finally be visited to as the war was finished off by a "black dragon Digimon". Perhaps Dragoramon had something to do with that short-lived war between the two Digimon races?