Demons

Demons are the original inhabitants of the Hell Planes. They are similar to Elder Gods in that they are bundles of Source energy, but have a set physical form and are far weaker (Super Weight 1-4). The Archdevils have subjugated them and have perfected the ability to fashion them out of damned souls. Demons come in a myriad of forms, but can be grouped into a few broad types.

Baatezu
Demons native to Baator are called baatezu. They are beings of order as well as evil, and developed a highly regimented society on their home plane under Asmodeus. Unlike other demons, they were servants of the Elder Gods who sided with the Archdevils and were corrupted by their descent to the Hell Planes.

Baatorians
Baatorians are the original demons of Baator, and like the baatezu were beings of law. They were the only demons to resist the obyriths, but were almost completely exterminated by Asmodeus and the baatezu.

Obyriths
The obyriths are ancient demons of chaos native to the Abyss. Unlike other demons, they do not usually look even remotely humanoid. They were fashioned out of Source energy by the Queen of Chaos, one of the Great Old Ones. Under her leadership they conquered the Hell Planes and many other realms. After her imprisonment, they retained control of much of their empire and crafted many other types of demons before they were decimated by the Archdevils. A very few still exist, but they either serve the Archdevils or hide in the deepest pits of the Abyss.

Tanar'ri
The tanar'ri were the first demons created by the obyriths. Like their former masters, they are chaotic beings. They were used as slaves until they rebelled against their masters, which coincidentally happened only centuries before Demogorgon and Orcus invaded the Abyss. The tanar'ri willingly aided the two Archdevils in crushing the obyrith empire and are now the primary demons of the Abyss.

Yugoloths
Yugoloths are demons of pure evil, originally native to Hades. At some point, they migrated to Gehenna and established a powerful civilization there before they were forced to acknowledge the authority of the Archdevils. They were, however, allowed to retain control of Gehenna.

Other types
Hollows - Demons native to Hueco Mundo that form spontaneously from restless souls. Unlike other demons, they must feed on souls to survive. Powerful Hollows eventually develop a taste for their own kind and ultimately merge into a mindless Gillian Hollow. Sometimes, the personality of one of a Gillian's component Hollows takes over, allowing it to feed on other Hollows in order to ascend to Adjuchas and finally Vasto Lorde Hollows.

Rakshasas - A type of tigerlike demon with several subspecies. The obyriths fashioned them from the Source energy of several Hell Planes, and as such they do not really have a home plane.

Night hags - A form of demon native to Hades. They are highly skilled in magic and are the plane's dominant species.

Chaos spawn - Demons native to Tiamat's plane, the Sea of Chaos. They are all descended directly from the goddess and come in many varieties.

Demon lords
Demon lords are incredibly powerful unique demons. How such demons come to be varies; some were created that way, and some were formerly normal demons that cast off their previous form and ascended to a new level. Only the five main demon types can ascend to demon lord level, although Hollows reach a similar, albeit somewhat weaker, level of power at the Vasto Lorde stage. The demon lords below are listed in order of power.

List of demon lords
Baatezu lords: Bel, Dispater, Mammon, Fierna, Belial, Levistus, Glasya, Baalzebul

Baatorian lords: Baalphegor, Zargon

Obyrith lords: Pale Night, Pazuzu, Dagon, Obox-ob

Tanar'ri lords: Juiblex, Baphomet, Yeenoghu, Malcanthet, Zuggtmoy, Fraz-Urb'luu, Graz'zt, the Shadow

Yugoloth lords: Phraxas, Mydianchlarus, Diablo, General of Gehenna