Demonstrating all the virtues, The Stranger delved into the Great Stygian Abyss, where the Codex of Ultimate Wisdom was unveiled and where the Skull Of Mondain was dropped into. From that point on, The Stranger was then known as the Avatar.
Approximately ten years after The War of the False Prophet, Sir Cabirus founded a colony of diverse races within The Stygian Abyss; Baron Almric oversaw jursidiction from his castle nearby. Some years after the colony fell into ruin, The Avatar found himself summoned to Britania by the ghost of Garamon.
The Avatar returned to Britannia because of the ghost Garamon in a dream had claimed that a "great evil" was present in the Abyss. After being transported to the Isle of the Avatar, the Avatar was thrown in the Abyss, falsely accused of kidnapping Baron Almric's daughter, Arial. While in the Abyss, the Avatar fought and made peace with some of the monstrous and civilized folk, and collected Cabirus's eight Talismans of Virtue. The Stygian Abyss is unique in all of Britannia, because the barrier between dimensions is especially thin. As it turned out, an evil demon called the Slasher of Veils was brought into this realm by a foolhardy wizard named Tyball. The Avatar rescued Arial and used the talismans to banish the creature. This set off a volcanic eruption that completely destroyed The Abyss and the surrounding settlements on the Isle of the Avatar.
The most powerful residents of the Abyss were two brothers named Tyball and Garamon. They were mages but did not dwell among the mages of the sixth level; they were powerfull enough to dwell upon the seventh and eighth level, being little concerned with the danger posed by monsters here.
Their great interest was in planar travel - the possibility of moving through the veils between worlds. They finally succeeded in tearing through such a barrier ... to their ultimate misfortune. When they pierced the barrier between dimensions, a monster stepped through from the plane of demons. The brothers called this creature the Slasher of Veils.
Powerful on its own world, it hat the potential to become equally powerful on Britannia, but in the moments after it arrived it was weak by demonic standards. The brothers, horrified at what they had accomplished, were able to bind it, but were not able to send it back whence it came; it resisted their efforts. The brothers immediately began new research so that they might correct their grievous error.
Tyball and Garamon developed a plan. First they would build an imprisoning chamber and imbue it with virtuous magic. Second, Garamon would lure the Slasher of Veils into the chamber, where it would be weakened by the virtuous energies there. Third, Tyball would shut the two of them into the chamber. Fourth, Garamon would rip open the veil to the demon's own plane and lead the demon through. Fifith, Garamon would escape through a portal already placed in this dimension, leaving the demon trapped there; activation of the portal would seal the rips in the veil, denying the demon a chance to return to Britannia.
With speed born of desperation, the brothers began to work, preparing the Chamber of Virtue and making very cautious, furtive trips into the demonic dimension, where they prepared Garamon's path to safety and the portal allowing him return to our world.
But the demon, too, was at work. It correctly divined that Tyball was less virtuous of the two brothers and began to speak into his thoughts. It gave him knowledge and promissed more. It promised wealth and power, greatness and majesty. All Tyball had to do was let Garamon lead it into the chamber of Virtue and watch as the demon ate Garamon. The Slasher of Veils would then emerge from the Chamber of Virtue, shut it forever (that its virtuous nature not infect the Abyss); then Tyball and the Slasher of Veils would become partners in destruction.
On the day of the ceremony, the demon was brought before the Chamber of Virtue. The brothers freed it from its crumbling bonds, and Garamon uttered a challenge and insult so great that the demon was obliged to kill him. Garamon ran into the Chamber of Virtue, the Slasher of Veils at his heels, and called for his brother to shut the chamber door. But Tyball did not do so; he merely smiled and told Garamon of the greatness that was to come, of the ruin that was to befall Britannia. The Slasher of Veils began methodically to murder the virtuous brother.
Dying, Garamon was still not without great power. Yet if Britannia were to survive, he could not afford to use his power to defend himself. Instead, he cast a mighty spell which, despite Tyball's best efforts, drew closed the door to the Chamber of Virtue. The demon was bound in place, but Garamon was not. His act of sacrifice made him virtuous enough to leave the Chamber of Virtue, and so he did by magic; but he died immediately thereafter, and his remains were lost on the lowest level of the Abyss.
Tyball was outraged by this turn of events. His brother was dead, his patron was imprisoned, and he, Tyball was as far from ultimate power as he had ever been. Nor could he open the door to the Chamber of Virtue; all virtues had fled him. He turned again to research, trying to determine how he might open that stubborn door.
As it turned out, there were three ways to do this.
The first was to become utterly virtuous; the door would then swing open to a gentle push of the hand. But utterly virtuous men and women are rare, and it was now impossible to cleanse all the stains from Tyball's soul.
The second was to find the three legendary keys, the Key of Courage, the Key of Love, and the Key of Truth, and bind them together into the Key of Infinity, an item imbuing enough virtue to open the chamber door. Tyball briefly considered this quest, for the Keys were thought to be in the Abyss; but then he learned about the third way, and chose it instead. This third way was to find someone of great virtue -- perhaps not of sufficient virtue to open the door himself, but of great virtue nonetheless, and a virgin besides -- and sacrifice that person after a lengthy ritual before the chamber door. The sacrifice would shatter the virtue of the chamber and reopen the rent into the demon's dimension.
Naturally, Tyball chose the third means.
He begrudged the amount ot time it would take to find someone virtuous enough, but was in luck: The sterling character of Arial, the daughter of Baron Almric, was well known throughout Almric's dominion. Tyball took a troll-minion to Almric's castle, used his magical powers to appear within the girl's chamber, and rudely stuffed her into a sack, which he then dropped out the window to the waiting troll. At this point, nothing stood between him and ultimate victory.
Then it was that the miracle occurred: The Avatar returned from otherworldly wandering, appearing in that self-same bedchamber, drawn by the ghost of Garamon; for Garamon chose the famous Avatar to oppose Tyball. Tyball eluded the Avatar at that time ... but not for long. And for this we can all be grateful.
The Skull Of Mondain is still said to exist in the Abyss, waiting to be found by anyone unfortunate enough to stumble upon it.