The Lower Plane of Infernia, the Realm of Demons, has been catalogued by sages in outer planar theory as well as various specialists with the Knowledge (the planes) skill as having manifold layers within a single plane. Some layers are thought to be of infinite size coexisting and overlapping the existing planes while others are quite finite in size and space.

The exact number of these various layers is unknown. Most scholars believe that Infernia is most likely infinite in size and only a very small number of these layers have actually been visited by travellers from the mortal realm of the Prime Material Plane. Below is a very brief description of some of these known layers of Infernia:

Layer 1 Gateway- The layer known commonly as 'the Gateway' is the first and 'uppermost' layer of the plane. It is the common entry point into Infernia from the Prime Material. The Gateway is also the layer linked to the other Lower Planes via the River of Death which flows across its scorched and hazardous plains. The Gateway is said to also have numerous conduits that lead deeper into the Realm of Demons reaching many of the other layers. The Gateway is a layer of vast wasteland, active volcanoes, deep craters and choking ash. Many of the various subtypes of demons dwell in this layer and it is often the starting point for major campaigns in the Blood War.

Level 3 Gardens of Vice- The third layer is a land of steamy rain forests thick with vegetation and deadly jungles. The air is scented with the sweet smell of tropical blossoms many of which are quite deadly to beings not native to this plane. The layer is home to the succubi and is the Throne Layer of their queen, the demoness Demoriel. It is a plane of temptation where strangers to the plane are sometimes taken and drained of their life energy.

Level 13 Aerie of Baleful Breezes- The 13th layer is a region of high, rocky mountains, crags and seemingly endless windswept skies. The layer gets its name from the ill-winds and violent tempests that continually blow across the layer. The Aerie of Baleful Breezes is heavily populated by the vulture-like demons known as the vrock. It is also the Throne Layer of the demon lord known as Mirihim, the demon prince of pestilence and lord of the vrock.

Level 51 Sea of Drowned Souls- The 51st layer is a great watery layer cursed with the foul stench of death. The layer is home to many demonic horrors and aquatic nightmares and is dotted with many islands of varying size. Souls of chaotic evil pirates that drowned at sea are known to haunt this layer. It is also believed to be linked to the 450th layer known as the Blood Sea.

Level 98 Pale Darkness- The 98th Layer is a land of fading light and burgeoning shadows and a region of perpetual twilight. The layer is haunted by undead shadows, infernal shadow dragons and similar such creatures. The layer is controlled by the demoness Sheolba, goddess of the dark elves and the dark elf petitioners dwell here in numbers to numerous to count.

Level 99 Shadowpits- The 99th layer known as the Shadowpits is a rocky layer of deep fissures and endless night. Its oppressive darkness weighs heavy upon all who visit this layer like a wool blanket cloaking the landscape. It is this layer that serves as the Throne Layer for Sheolba and where dwell the majority of the dark elf petitioners.

Level 450 Blood Sea- The 450th layer is a watery layer of endless depths. It is home to many aquatic monsters and water demons. Areas of the Blood Sea are stagnant and foul but all of it is the color of blood perhaps from the many sacrifices conducted in the name of many of the demon lords. The Blood Sea is the Throne Layer of the gelantinous demon Ocanthis, the Lord of the Ocean Abyss.

Level 500 Battleplains- The 500th layer is a region of great violence and constant death and bloodshed. The layer is surely the perfect home for its foul lord, the demon prince Dheragos, General of the Infernal Armies and a major patron of the Blood War between the demons of Infernia and the devils of the Gloomrealm. Vast fields of rusting armor and weaponry lay scattered throughout the layer.