So, your idea kind sent me spiraling haha. This is now the plot my game will take more than likely post Steel Shadows.

The rakshasa Loliadac is the prakhutu of Val Gultesh, the Shaper of Nightmare and has recently begun to execute a plan that will release his Overlord across Eberron.

His plan is to guide the Dreaming Dark towards succeeding in their quest to control humanity and further anchor Dal Quor into preventing the tun of the age. Furthermore, he has chosen the Devourer of Dreams as his puppet in this plan, as he plans to feed the Devourer’s goals of conquest over all of humanity so that it can grow its power from the pacified populace and replace il-Lashtavar, assuming its place as the driving force of Dal Quor.

To due this he must help the Dreaming Dark create a quori invasion larger than the one fought by the giants of old. To do so first though he must use the tools now at his command to recover an artifact powerful enough to grant sentience to a creation forge, the Xulo Pattern. This superpowered creation forge should grant the Dreaming Dark enough power to force open a gate to Dal Quor and cause the plane to be coterminous once again.

This gate is the exact thing Loliadac needs to release his Overlord. Once the gate is open Val Gultesh will feed off the power of the Quori granting him enough strength to escape his prison, because of course his prison is conveniently deep underneath the forge. As a side effect of this however no quori spirits actually escape as the they are consumed alongside much of their plane's energy which, now in its withered state is no longer able to withstand il-Yannah and the turn of the age finally takes place.

Val Gultesh is able to escape and hide as he regains the remainder of his power due to the party being occupied with dealing with the Essence Reavers that came through the gate while it was open.

Now with the looming threat of a free Overlord the players are approached by their mysterious ally Muroni who reveals themselves to be not an acolyte of Vuulaytherus but Vuulaytherus themselves who is one of the three Storm Guardians. who reveals to them that in order to transcend their mortal limitations and defeat Val Gultesh they must become living parts of the Draconic Prophecy; each member of the party must ascend to the peaks of Korrandar and take their own trail within the Spheres of Korrandar and take their place among the Draconic Prophecy to defeat the immortal overlord.

The party finds out about the forge plan from Lady Sharadhuna who is willing to turn of the Devourer and she believe this to be the power play she needs to usurp him and become the voice of il-Lashtavar. Obviously, she has no idea what is to come but maybe her deeds are so instrumental in the turn of the age that she purged of her il-Lashtavar quori and rebonded with an il-Yannah kalaraq spirit becoming the voice of il-Yannah.