The origins of demons and devils is hotly debated by scholars with no one really knowing the true origins of these powerful entities.
Scholars debate on three popular theories on the origins of devils and demons.
The most prominent theory is that they are an ancient power, even older than the gods, that have always existed. They were the ones that created the world and the gods arrived and usurped them. This is what a demon or a devil would tell you but they are all deceitful, so it is hard to take them for their word.
Some believe they were created by the gods in an attempt to reign in the dragons during the height of the dragons power. It is said the fiends deceived the gods and broke free from their control and carved out their own kingdoms in the outer planes. Which would later be known as the Nine Hells and The Abyss.
Another common debate is that they arrived from another plane of existence. At some point in the past, a connection formed between the two planes which allowed them to pass between worlds. When the gods discovered the connection, it was severed and the demons and devils that had already crossed over were trapped here.
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Demons are beings of true and pure chaotic evil. They have no regard for right or wrong, they live to destroy all things. There is no semblance of order of any kind in the Abyss where they hail.
The Abyss has infinite layers and each layer is ruled by the most powerful demon on that layer. Every demon strives to conquer the layer above it. The top 12 layers are the realms of the Demon Lords. The Demon Lords are the 12 most powerful demons in existence and they rival the power of a lesser god.
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Devils are cunning and tactical. They are lawful evil in their nature and follow a strict militaristic like hierarchy. Nothing a devil does is without careful thought and planning. They make their home in the Nine Hells. Each level of hell is ruled by an Arch Devil and every subordinate on their level strives to overthrow the current leader and take their place. An Arch Devil's power rivals the power of a lesser god.
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The Abyss and the Nine Hells float aimlessly in an endless void. They sit across from one another, separated by the Stygian River that flows in the shape of an eight, encircling each realms and keeping them separate.
At the very center, the intersection where all branches of the river meet, is the Cauldron. The Cauldron is a writhing mass of corruption, filth, and despair. A twisted and grotesque collection of blood, malformed limbs, slimy tentacles, and putrid foulness. Squirming souls claw their way in desperation to the top, only to be dragged back down by grasping hands and writhing tentacles, to be smothered in the foulness.
The Cauldron is where the souls of deceased warlocks end up after they pass from the mortal world, the corrupted souls of the faithless, and the souls of demons and devils that have been defeated also end up in the Cauldron to fight and claw their way to the top of the rolling mass of souls and filth.
An individual's soul that is in the Cauldron could take many hundreds of years to claw their way to the top and free themselves, but that is just the beginning; Once free from the Cauldron they are reborn as the lowest form of demon or devil and then must still continue their fight to survive and ascend the ranks.
A soul that escapes the Cauldron is reborn as the lowest caste of demon or devil. They will becomes a slug if they are reborn as a demon or a skulk if they are reborn as a devil.
The soul of a demon or devil will be reborn into whichever of the two they were in their previous life. A warlock will be reborn into whichever race their patron was.
A corrupted and faithless soul will be reborn as whichever race corrupted them, whether that be a demon or a devil. Additionally, they will be marked to serve that demon or devil once they escape the cauldron.
While in the Cauldron, a soul is fully aware of who it was and they can recall every detail of their previous life but none of that helps them in their struggle to free themselves from the cauldrons currents. Once in the Cauldron, no life force is greater than any other regardless of their previous station in life.
However, once they break free from the Cauldron, the currents of the Stygian river sweep them away and all traces of their past life are washed away by the currents, then they begin the transformation into either a slug or a skulk.
Some time after the transformation is completed, they are washed ashore on the lowest layer of either the Abyss or the Nine Hells. They retain only obscure memories of their previous life and a vague sense that they were once something greater.
Their struggle up the hierarchy begins the moment they are spun out of the Cauldron. More often than not they will be killed once again and thrown back into the Cauldron before their ascent even really begins.
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Iz was a powerful arch devil that fell to the chaos of the abyss. He now rules the 1st layer of the abyss as a demon lord. Iz has become the most powerful demon or devil in existence. The greater gods even respect his power.
Iz slayed the previous ruler of the first layer, relegating him back to the cauldron. Using his formidable powers, Iz located the previous ruler when he was spun back out as a slug and he kept him as a trophy to torment until he became bored with the game and slayed him again.
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Demon hierarchy
Lesser demons
1 - A slug feels nothing but pain and hunger. It just wants to feed to end the pain. A slug will feast on anything it can cram into it's mouth including other slugs. It will feast and grow. Slugs have a swollen body with a pale, milky colored hide that is thick and shapeless and constantly oozes puss and excrement. Slugs wanders aimlessly on four twisted and stumpy legs in a constant quest to feed.
Despite it's appearance, a slug has a high intelligence and an awareness that it must survive and grow. Next to feeding, self preservation is the next highest priority for a slug. If a slug can use their cunning and intelligence to feast and stay alive they will be transformed into the next ranking of Demon.
2 - A wretch is the next level of demon in the hierarchy. They have an appearance similar to a large hairless bipedal dog. A wretches life is filled with paranoia. At this stage a wretch has much more awareness and fully understand the daunting task ahead of it. A wretch is a bully and will actively seek out slugs to torment. At this stage they are popular fodder troops for a demon higher up the rankings.
Intermediate demons
3 - A fiend is the third ranking of demon types. At this stage a demon will begin to resemble whatever it's final form will be. Demons have a bestial appearance and many of them have an amalgamation of features from a variety of species. At this stage they get a huge spike in their power and they bulk up significantly from their wretch form. As a fiend, a demon can start to do some real damage.
A fiend can even rule his own layer of the abyss but they are not yet powerful enough to grant powers to a warlock.
4 - Once a demon reaches the fourth stage and transforms into a cacodemon they take a large jump in power from a fiend and at this stage they can begin to gather warlocks and they take an immense leap forward in magical prowess.
At this stage they are nearly fully matured and developed. Cacodemons are a true force and a dangerous foe to any but the most skilled adventurers.
Greater demons
5 - An arch fiend is the fifth stage of demon. Now we are talking about a truly powerful being.
6 - Many demons do not make it beyond the the sixth rank which is balor. This is because the competition to become a pitlord is so fierce and the fighting is brutal.
7 - A pitlord ranks just below a demon lord and many pitlords rival them in power. A pitlord spends much of their time fending off balors and other pitlords as they attempt to ascent the hierarchy in the abyss, clawing their way up layer by layer.
8 - Demon Lord is the final stage and where a demon is fully formed and has all of their abilities available to them. There can only ever be twelve demon lords and to become a demon lord you must kill a demon lord and absorb their essence.
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Devil hierarchy
Lesser devils
1 - A skulk is the first level of a devil. They are spindly creatures that resemble an emaciated and badly sunburned elf. They are cowardly and spend most of their time skulking in the shadows or tucked away in deep crevasses only to appear when something weaker than themselves happens by.
2 - An imp is the second level of devil and they resemble tiny gargoyles. At this stage, devils grow their wings and they gain some rudimentary magical abilities but they are capable of learning more powerful spells.
An imp demonstrates a lot of bravado and can be quite brazen. This can be attributed to their transformation from a sniveling skulk into a seemingly more capable and dangerous foe.
Imps are often recruited by higher ranking devils to do unsavory or menial tasks. An imp is the most commonly contacted and encountered of the devils. A relatively skilled spell caster can easily control them so they are summoned quite often.
Intermediate devils
3 - An infernal is the third level of devil. At this stage, Internals begin to look more imposing. They have a bulky muscular frame and their skin seems to roll across their body like a lava flow. Large wings droop from their backs and thick, black horns sprout from their heads.
This is the stage where most devils will begins to build their army. They will gather skulks and imps to their side as well as other infernals that are weaker than themselves.
Greater devils
4 - A balor is the fourth ranking of devil and will command many legions of infernals and their armies. At this stage a devil is powerful enough to accept warlocks. This gives them a huge boost of power and influence.
5 - An archdevil is the fifth and final ranking of devil.
Side note: At some point between the third and fourth ranking, a devil gains the magical ability of illusion and they seek out mortals to seduce. The devil will identify their target and decipher what most attracts and arouses them. The devil will then use their illusion magic on themselves to recreate the exact likeness that their target find most attractive. Every detail is recreated, even down to smell and texture.
When a devil is in this state they are known as succubus for females or incubus for males. Offspring can and are produced from these unions. They are known as cambions. Their birth to a mortal woman almost always results in her death and the death of the babe when it is discovered what they are.
On rare occasions there is an attempt to raise the child but by early adolescence they grow too violent to manage and they wield wild and dangerous magic that they cannot control. They are either killed or abandoned.
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The twelve demon lords -
1 - Iz "The Fallen" is a devil that fell to the chaos of the Abyss. He is red skinned and has delicate elven features. Iz rules the first layer of the abyss. The first layer is characterized by oppressive dry heat. A translucent red, fog-like haze drifts across a landscape filled with ochre streaked sandstone formations that seem to bend and shift as the fog rolls passed.
2 - Neflar "The Crucifix" a cloven hooved and boar headed monstrosity with jagged tusks jutting from his face at odd angles. Neflar rules the second layer of the abyss. This layer displays a chaotic landscape with blackened skeletal trees that have been bent and twisted to form profane runes and glyphs.
3 - Jelffilnay "The Demon Queen" is vaguely humanoid shaped and her entire body is covered in large leathery lumps that ooze a foul smelling oil. She rules the third layer of the abyss. This layer is rife with lava flows and volcanic activity. Geysers spew magma thousand of feet into the air only to rain back down across the landscape, sometimes miles away.
4 - Dretchnor "The Foul", one half of his body is a red puckered scar with a twisted and crooked arm jutting out at an odd angle. The arm appears to have been impaled into his side without much thought as to proper placement. The fourth layer of the abyss is his domain. This layer consists of jagged, obsidian formations reaches miles into the sky and razor sharp, shattered obsidian shards litter the ground.
5 - Hrnchnor "The Feral" is a filth covered, one armed and one legged beast-like demon. He shuffles around part crawling and part shambling, using his lone arm as a second leg to maneuver and move quickly. He rules the fifth layer of the abyss. This layer is an oppressively humid dark forest that is perpetually twilight. The ground is soggy and filled with biting insects and bottomless bogs. Walking around is near to impossible. A never-ending cacophony of howls and snarls can be heard throughout.
6 - Drengrozen "The Tentacle Lord" is a squid-like demon with lashing tentacles and a beak affixed to his face that can crush a large boulder in a single bite. Drengrozen rules the sixth layer of the abyss. This layer is a flooded landscape of briny saltwater. Many decaying corpses float around on the current and clump together to create islands of bloated corpses.
7 - Grazz'nix "The Tainted One" has a leathery and drooped face, slumped shoulders and pot belly. He rules the seventh layer of the abyss. This layer is characterized by a barren, grey and windswept landscape. Grey is the only color seen on this layer. Grey dust storms coat everything in a gritty grey film. It is flat and desolate as far as the eye can see.
8 - Slogath "The Plague-bringer" is a vulture headed and ape bodied demon lord that rules the eight layer of the abyss. His realms is a cold and desolate place with burning ice and snow. Great icebergs float on a sea of slush. Slabs of ice reach thousands of feet into the air. A glowing sun that never sets, reflecting an intense, harsh glare off the pure white landscape.
9 - Bogthrun "The Savage Scourge". One of his hands is a massive pincer and the other is a hooked claw. He sports a bulls head with a thickly muscled neck, and a lizard-like body. Bogthrun rules the ninth layer of the abyss. This layer consist of thick vines and weeds sprouting needle sharp, barbed thorns. Paths and opening present themselves only to close and shift as you pass through.
10 - Ozronoz the Ooze Lord, appears as a living puddle of slime. He is the ruler of the tenth layer of the abyss. His domain is a sticky and muggy swamp. Sweltering heat with no breeze as relief. The ground and pathways are filled with pools of toxic sludge and swarms of biting and stinging insects fill the air.
11 - Skrilniflix the Tormented, one side of her body looks like melted wax the other a goat. Her domain is the eleventh layer of the abyss. This layer is one of ice and blizzards. Blue ice formations dominate the landscape. The light reflecting off the ice casts everything in a pale blue glow. The shimmering and glowing blue ice distorts the sense of distance and confuses the brain.
12 - Grogemagthar "The Oppressive", a snake-like, scale covered body, with an old woman's head. Grogemagthar rules the twelve layer of the abyss. Drifting smoke and the smell of fire dominates this layer. No mater the direction you face the smoke always blows towards you, obscuring your vision and sense of smell. Sharp rubble and deep ravines are commonplace here. Burning and charred trees are present as far as the eye can see. Thick ash floats on the air to settle everywhere.
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When Dretchnor and Hrnchnor were spun out of the Cauldron they were conjoined from knee to shoulder and shared a third arm from the center of their chest. Dretchnor controlled the right side and Hrnchnor controlled the left.
When they reached the rank of pitlord; Dretchnor tore himself free from his twin and kept the third arm and the shared leg as his own, leaving Hrnchnor to die. Hrnchnor cursed his twins foulness and vowed to survive and reclaim his arm and leg.
Dretchnor soon after claimed a spot as a demon lord and began his ascent up the hierarchy. Hrnchnor fueled by hatred and revenge became like a feral beast and ultimately survived the devastating injury and began his own ascent of the hierarchy hot on Dretchnor's heels.
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Many warlocks that serve on ships at sea, often have their pact with Drengrozen the Tentacle Lord. He resides on a briny sea filled level of the abyss filled with rotting corpses floating aimlessly on the currents.
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The nine arch devils -
1 - Astrauth
2 - Irzos
3 - Obloth
4 - Jinath
5 - Svethlana
6 - Amata
7 - Tet
8 - Malrak
9 - Ulgal