I am currently playing through this adventure in my Eberron home campaign. Here is the Backgrond.
Erandis Vol, usually known as Lady Vol or "The Lich Queen", is the last heir of the House of Vol, the elven bloodline that bore the Mark of Death. Born to an elven mother and dragon father, Erandis was the hope of many to end the war between the dragons and elves. She is believed dead by most, but was brought back as a lich and is secretly the leader of both the Blood of Vol and the Emerald Claw. To further her own goals and powers Vol recently sought an alliance with Tiamat, Tiamat found this new alliance pleasing and made Vol one of her exalted—Vol enjoys her new powers greatly and has designs on becoming an exarch. Since Vol is already a Lich, the Dragon Queen decided to turn Vol into a unique undead creature: a demilich!
Hungry for even more power to further her own goals, Vol wasted no time in proving her worth to Tiamat by hatching two brilliant and intermingled plans. Zehir, the god of darkness, shares the astral domain of Tytherion with Tiamat, and the two constantly battle for supremacy there. Bahamut is the natural enemy of Tiamat, and has been since the end of the age of dragons. Vol thus created a scheme to siphon off much of Bahamut's power and pass it to Tiamat, hoping that Tiamat could use that stolen power to drive Zehir from Tytherion.
Though few know this, Bahumat was in fact one of the first in those ever so ancient times to find the power of The Silver Flame. Those few on Eberron who are in the cult of Bahumat call The Silver Flame "The Breath of Bahumat." Vol has used her new abilities and a cadre of servants to coordinate attacks on highly placed mortal followers of Bahamut and The Silver Flame killing them and stealing any relics or other items that had been dedicated to the Platinum Dragon or The Silver Flame. When the souls of these slain followers attempt to speed toward their final resting place in Celestia. (For the followers of the Flame do in fact not go to Dollurh but to Tytherion to join there with The Silver Flame,) Vol uses the magic of the stolen relics to draw those souls to Tiamat's domain in Tytherion instead. The resulting influx of power is being funneled into an army preparing to strike Zehir's forces when its strength is fully realized.
I'd like to know what evryone thinks and if you have any comments feel free to let me know. I am planning on editing more adventures for my own use and will post them if there is interest.