Asmodeus

Asmodeus, an archdevil before the Spellplague, Supreme of the Nine Hells (or Baator), was the god of sin. An ever ambitious and careful creature, Asmodeus retained his position all through the Reckoning of Hell, unlike many of the other archdevils. Asmodeus was lord of Nessus, the Ninth Layer of Hell, though he was generally recognized as lord of all of his divine dominion of Baator, which lay within the Astral Sea.
Asmodeus was the undisputed master of the Nine Hells, commanding fear and respect from all those who occupied his realm. Even the gods who dwelt in the Nine Hells gave Asmodeus his proper due. Though the archdevils might work to usurp him, few had the courage to act openly. Asmodeus’s machinations were long in the making, and they might take centuries, if not millennia, to see resolution. He worked on a grand scale, carefully constructing insidious and inexplicable intrigues, maneuvering the forces of wickedness like chess pieces on a board that encompasses all the planes. His core concerns were simple. First, he wanted the power structure currently in place to remain exactly as it stood, with him in charge. He had spies on every layer, planted in every court. No fiend knew for sure which of its minions actually served Asmodeus, so the climate was one of justified paranoia. Asmodeus also expanded evil. He directly opposed celestials and good-aligned deities. His minions combated the agents of the Celestial Planes, murdering them whenever and wherever they could. Finally, Asmodeus waged war against the demons throughout the period of the Blood War. He saw the untold legions as a direct threat to his supremacy. Asmodeus was aware of every plot hatched against him. Older than the oldest archdevil, he watched the rise and fall of other archdevils far craftier than any of Asmodeus’s contemporaries. He kept to himself, letting his minions stew in fear of what he would do next. Of course, few forgot that Asmodeus emerged unscathed in the Reckoning, proving to all that he was their better. On the Prime Material Plane, Asmodeus had more cultists than all the other archdevils combined. Mortals who worshiped devils actually drew power from Asmodeus. He influenced all levels of society and had followers of nearly every race, even within the strongest bastions for good. His path was the way to great and unattainable power, so his clerics were mighty men and women with influence and personal magnetism that made them natural leaders among their kind.
Description
Asmodeus was depicted as the strongest, most cunning, and most handsome of all devils. Usually he appeared as a handsome, dangerous thirteen-foot-tall human with lustrous skin and black hair, his crimson eyes shining with internal power, his forehead crowned by a pair of small, sharp horns. Beneath his finery- red and black robes studded with black diamonds and fiery rubies of unimaginable expense- Asmodeus’ body was covered in bloody wounds sustained when he fell from heaven. These wounds oozed blood daily; the drops of his blood which touched the ground grew into powerful devils and demons.
Asmodeus was never seen without his Ruby Rod of Asmodeus, seemingly made of a single carved ruby that shone with the power of Hell; it not only served as a badge of office, but contained great powers, allowing Asmodeus to attack with elemental forces, force his enemies to cower in fear, or cover himself with a field which healed and protected him.
Abilities
Like the other archdevils of Baator, Asmodeus had the ability to cast many spells at will, and it was nearly impossible to hurt him without the use of very powerful holy magic weapons. Asmodeus’ Ruby Rod allowed him to use several powerful offensive and defensive spells at will. In addition, Asmodeus had the power to alter the form of lesser devils, including the other lords of Baator. He transformed Mammon into a humanoid/serpent hybrid, and cursed Baalzebul with the form of a gigantic slug with tiny, useless arms.
History
In the Book of Vile Darkness, it is stated that while Asmodeus is the oldest devil in the Nine Hells, he may not be the original ruler. However, the origin myth which appears in Fiendish Codex II: Tyrants of the Nine Hells contradicts this. According to the Codex, Asmodeus began as a servant of the lawful gods. Asmodeus is described in some versions of the myth as an “angel” (though this is self-contradictory given the time period during which this would have occurred). He was “the bravest, toughest, fiercest and most beautiful of angels.” He and the other angels were created to fight the demons of the Abyss, so that the gods could concern themselves with creating worlds and sentient beings.
After eons of fighting the creatures from the Abyss, Asmodeus and some of his fellows began to change. They grew similar in appearance and methods to the demons which they fought. Afraid of his power and of the changes he had undergone, the gods put Asmodeus on trial and demanded that he be cast out of the Upper Planes. However, he argued effectively (and correctly) that he and his fellows had not violated the law. Asmodeus and his followers successfully sued for access to the Upper Planes and the honors to which they were entitled.
Once the gods created worlds and sentient beings, the demons attacked these, too. The gods created mountains, oceans, and wastelands to seal up the gates to the Abyss, but their creations defied their orders and explored their worlds, accidentally unsealing the gates. The gods could not understand why their creations did not follow their instructions, until Asmodeus explained to them that their system did not work because it relied solely upon voluntary compliance. Asmodeus explained that the only way to ensure obedience was to threaten mortals with a disincentive; hence, Asmodeus invented the concept of punishment.
Asmodeus convinced the gods to sign a contract called the Pact Primeval. This contract allowed Asmodeus and his fellow devils to take up residence in the abandoned realm of Baator, to punish the souls of wicked mortals, and to extract magical energy from the souls under their care in order to fuel their powers. Otherwise, Asmodeus reasoned, they would have to be granted the powers of godhood in order to do their job, which the current gods would surely find unacceptable.
At first, the gods found the arrangement agreeable. However, they eventually realized that fewer and fewer mortal souls were ascending to the Upper Planes, and Asmodeus was deliberately tempting mortals to damnation. When they arrived in Baator, the gods found that Asmodeus had turned it into a nightmarish world of endless suffering, filled with countless new devils. When called to account for his actions, Asmodeus uttered the famous words, “Read the fine print.”
This story is presented as mythology, and the Codex itself admits that it does not tell the whole truth. For example, it is known that Asmodeus did not depart from the Upper Planes under amicable circumstances: He was cast out, and literally fell into the Lower Planes, sustaining serious wounds which have never healed. Part of Asmodeus’ long-term plans includes using the magical energy harvested from souls in order to heal his wounds, and ultimately, the complete destruction of the Upper Planes.
The names of the “gods” involved seem to change depending on what world and source the myth is told on, and some aspects and versions of the origin myth contradict others. For example, the version told in the Fiendish Codex II states that St. Cuthbert became a distinct deity when he agreed with Asmodeus that “Retribution is the basis of all law,” while the Deities & Demigods sourcebook states that he is a mortal who ascended to godhood.
The Manual of the Planes suggests a similar but different story. According to the section about the Nine Hells, Asmodeus’ true form is that of a giant serpent, hundreds of miles long. He was cast out of the Upper Planes before the creation of the current gods, and his fall created the 8th and 9th planes of Hell. He is currently still recovering from his wounds in the pits of the 9th level, and his devil form is just an avatar of the real Asmodeus. No one who tells the story of the true form of Asmodeus survives more than 24 hours after the telling.
When Dweomerheart collapsed in the wake of Mystra’s death, her servant Azuth fell into the Hells where Asmodeus, sensing his opportunity, devoured the lesser deity and became a god himself. He then ended the Blood War by forcing the Abyss underneath the Elemental Chaos.
These differing accounts of both historical fact and mythical context do serve one common end: the confusion created of the two serves as an effective veil from behind which Asmodeus freely operates. Some speculate many of the contradicting stories were spun by the arch devil himself, though thus far, nothing more than the existence of conflicting accounts supports as much.
Still, the nine hells and Asmodeus are alive and thriving in the wake of chaos. Many argue that is proof enough of the God of Sin’s continuing influence.