A certain interested party in Scornubel relayed a description of the ritual performed under Wyrm Wood and expressed a desire that any findings should be relayed to you. Initial reports from scholars confirm that a strange dementia affects the Yuan-ti, driving the millennium old race towards murder and mass suicide on an unprecedented scale. Obviously, a spell of such magnitude- one whose equal hasn’t been performed since the fall of the Netheril Empire- causes great alarm among our order.
Oghma’s adherence to details has led us to conclude that gaining the entity a corporeal form was not the ritual’s true purpose. In all likelihood, Thelek may have planned the effect (possibly another result of his followers transferring their powers) to coincide so as to disguise his true agenda.
As to the spell’s actual effects, I believe we have found a possible candidate of the ritual. The Netherillian tome Kevlsas Hollaew Urs, or Constant River, alludes to a massive alteration spell nick-named “Bending the Oxbow,” which was constructed to delve the extent of fate’s hold on reality.
Previous to the spell’s castings, all attempts to change an ordained future had met with failure. Any attempt to circumvent an undesired event would serve the future to manifest in an alternative manner. Minor changes could be made but the ultimate destination remained the same. Dismissing efforts to contruct alternative futures as foolish ventures, Netheril mages coined the phenomenon “Taking an Oxbow.” Fate, they concluded, could not be avoided.
Yet an order of Archmages known as The Cowled Nine sought an alternative approach. Fate, they posited, was unavoidable only because any effort to change it by a terrestrial being had already been accounted for. Therefore, an outside source of change might force the future to reshape itself.
The Cowled Nine spent the greater part of their magical arsenals and fortunes designing a ritual that would temporarily create a pocket dimension. While the dimension would, for most intents and purposes, be an exact mirror, it would be entirely new and therefore unbound by the same past and future as its progenitor. Sacrificing the sanity of the Caellons(a sentient race of homonculi manufactured by the Netheril) to fuel their magicks (a direct correlation to the yuan-ti), the conclave reportedly created a new “Faerun” for a little over five minutes.
In the “pocket world,” the copies of the Nine committed acts contrary to the result of former divinations, such as smashing an urn shown by their augurs to exist hundred of years later. They theorized that when the two worlds merged back as one, one fate would either subvert or incorporate the other. Thus allowing the possibly of new outcomes.
Despite their new take on Oxbows, the Nine’s experiments reached the same conclusion as their predecessors. When the two worlds became as one, divinations revealed that an individual seeking to revive the Caellons would later piece the urn back together. Likewise, all other alternations were incorporated into a new “weave” without any significant change. While the Nine concluded the ritual a success, they abandoned future experiments as cost-inefficient when results would likely be the same.
If my theory proves correct and Thelek did indeed cast the Nine’s ritual, he undoubtedly disagrees with the conclusions drawn by the Netheril. Since you did not describe any temporal or planar displacement, I can only assume the entity is delaying the spell’s effects for a more appropriate time. He seeks to change something; that much is clear. While Thelek is unlikely to succeed, I am not so easily convinced he would be satisfied with a single attempt.
Distracted by Caprul Amrin, I believe our order ignored the greater threat. You now have our full attention and capability at your aid. Envoys have been dispatched to the clergy of Torm and Illmater. No longer are you alone. My only hope is that we are not too late to rectify our oversight.
Jurius Morley, Keeper of Tomes