Dawn Cataclysm

Legend
The following excerpt is from Rhyester's "Sermon of the Eclipse," written in the Year of Drifting Stars (760 DR) Historians have tried and failed to date the Dawn Cataclysm, though most agree that it unfolded after the fall of Netheril and heralded the fall of Myth Drannor. Some say it occurred before Mystra established the office of Magister some seven centuries ago, while others insist that it happened after Azuth battled Savras for supremacy in service to Mystra. Some claim it unfolded in the Year of the Hangman's Noose, when the last Chosen of Tyche died nine times in a single year within the vinelike coils of Moander's avatar. Still others believe that the recent schism in the Church of Tyche is a direct result of the former Lady Luck's corruption during the Dawn Cataclysm.

Pieces of The Puzzle
The Roll of the Years
 * -339 DR The Fall of Netheril The transformation of Mystryl to Mystra
 * -255 DR Jhaamdath Falls
 * 136 DR Reign of second Magister
 * 161 DR Year of the Hangman's Noose
 * 171 DR Moander sealed away in Yulash
 * 261 DR The Founding of Myth Drannor
 * 714 DR Fall of Myth Drannor
 * 760 DR Sermon of the Eclipse

A Candlekeep Sage's Argumentative Conclusions

 * Azuth was the First Magister, an office created by Mystra, not Mystryl.
 * Azuth and Savras were mortal during the same time period and most likely from highly magical civilizations. Azuth quite possibly hailed from Netheril or the Survivor States. Savras was a "Southern" mage, he may have been from Zakhara, Mulhorand or a survivor of Netheril fled to Halruaa during its creation.
 * According to Faiths and Avatars: Azuth and Savras were rivals for centuries.
 * Azuth must have already been Magister when he battled Savras, because the end result was Azuth's Ascension and Savras imprisonment in the Scepter of Savras. Volo states "After the fall of Netheril and before the founding of Myth Drannor, the Gods of the Realms battled in the Dawn Cataclysm" further more: "new deities were created and Tyche was sundered into Tymora and Beshaba." During this time of turmoil, two Gods elevated by Mystra to oversee the portfolios of wizardry battled for supremacy.
 * CONCLUSION: The Dawn Cataclysm was probably sometime between the years -39 DR and 130 DR. It could not have been the Year of the Hangman's Noose (161 DR), since that year there was a fourth Magister. The last Chosen of Tyche may have died nine times in Moander's coils (euphemistically), but it was probably a denial period of the clergy (like Bane to Cyric after the Time of Troubles). If Azuth had been rivals for centuries with Savras and Magister for even one century, that would put the time at 300 years minimum from the fall of Netheril. Special Note: Although there is no definitive proof, Amaunator probably made the transition to Lathander during this time period (albeit very slowly).