Geryon is a Greek giant, not anything Goetic. On that subject, I strongly suggest we steer clear of original real-world sources for fiends and the like.

Now for something fun that I worked on some time ago: my take on the Dawn Cataclysm.

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• The Dawn Cataclysm was a period of Faerūnian history that took place over a few hundred years, beginning around, loosely, -350 DR.

• The root causes of the Dawn Cataclysm are numerous, but the most predominant are three:
• The ascension of the Dark Three through the machinations of the Netherese deity Jergal.
• The fall of Netheril through the folly of Karsus.
• The emergence of Lathander, called Morninglord, a power of renewal.

• Whether Lathander emerged from the death of Amaunator, the Netherese sun god, or was present before in a different pantheon (the Talfiric, perhaps) and coexisted, is ultimately difficult to say. One prominent theory held that Lathander, Amaunator, and Jergal represented the dawn, the midday, and the dusk, and that only two of the three could hold sway at any one time. If this is true, then the emergence of Lathander at the same time that Amaunator fell and Jergal voluntarily diminished himself may have disrupted the cycle and the balance of three.

• The Dark Three were active during the time of Netheril, and likely began to forge their cults and churches in the strife and death of the fall. This surge in prominence of three new faces of evil was a cause for alarm among the powers of Good, as the Dark Three lacked for subtlety, hungering to set upon the world as its new rulers.

• Lathander viewed the fractious pantheons of Faerūn as stagnant and sedentary, unable to respond to the evils of Bane, Bhaal, and Myrkul. He urged his followers to spread forth from their lands, making contact with the followers of deities from other pantheons. Lathander attempted to convince these gods that they needed to change, or they would fall under others who were more adaptable. He exhorted them to follow his example - and to follow him, as the leader of a united pantheon of goodly and rational deities against the upjumped mortals now threatening to bring the world to heel.

• Some deities were eager to join him, concerned about the strength of evil. Others were resistant to uniting with other pantheons, concerned that their portfolios would be at risk. Some were actively encouraged by the concept of predating on deities from other pantheons in order to seize more power for themselves.

• These divisions happened not between individual pantheons, but within them. The god Auppenser was supreme among the Jhaamdathan pantheon, and would not hear of kneeling to the Morninglord, concerned as he was about protecting the psions of his land. Factionalism among the gods caused division in the Jhaamdathan pantheon, resulting in a coup in Jhaamdath that installed a vicious warmonger in place of the old rulers.

• With the gods of war eagerly unleashed upon one another, the gods of storm and fury came forth to bring havoc. Lathander's crusade had transgressed the traditional boundaries of the pantheons, and the fragile peace shattered as gods of all stripes struggled to cement their roles in the free-for-all.

• When the dust cleared, it became evident that whatever Lathander's actual goals, he had missed the forest for the trees - the most ancient evil of Toril, Shar, had undermined his efforts from the very beginning, using the kinds of foe he would immediately perceive as the greatest threat (new gods, young and active, like himself) as a diversion while she helped strengthen other forces of darkness. A dreadful ocean goddess, Umberlee, was summoned by elves into the Sea of Fallen Stars, where she seized and drowned the last defender of Jhaamdath, the reason goddess Murdane, capturing the inland sea within her portfolio and establishing herself as the predominant deity of all the waters. The foul demiurge Moander deceived and corrupted Tyche, goddess of fate, forcing Shar's rival Selūne to salvage a lesser goddess of good fortune from the putrefying essence of her friend while unleashing a cruel goddess of misfortune upon the Realms. The battles of gods with similar portfolios had greatly empowered forces such as destruction and war, seating Tempus and Talos as greater gods with wider sway over the Realms.

• The ultimate outcome of the Dawn Cataclysm was a united Faerūnian pantheon, with many gods much greater in scope than they had been previously. Lathander obviously did not get to renew the world entire without the stain of darkness, nor did he become leader of the united pantheon or otherwise achieve his aims.


Bear in mind this has traditionally been a big sucking empty gap zone in Faerūnian history and this is wholly loose inference on my part.