The Dark Nebula, also known as the Evil Range, is a nebula located in the Gradius universe.
For years, the Dark Nebula was prohibited from entering by the Gradian government due to it being a dangerous nebula. In 7040, a Gradian science vessel disappeared in the Dark Nebula. Soon afterwords, an evil force known as the Original Visions of Ultimate Monster sent invaders to attack the planet Gradius and its seven colony planets. Unfortunately, Vic Viper, Lord British, Falchion Beta, and Jade Knight penetrated the Dark Nebula, invaded O.V.U.M.'s fortress and destroyed the evil force, returning peace to Gradius.
The inhabitants of the Dark Nebula are very similar to the Bacterians. This leads to the apparent conclusion that they are the same amoeboids that have fought Gradius for years.