Sleep, Ye Cursed Child -- A fantasy adventure for 17th-level characters is the tenth adventure in the War of the Burning Sky campaign saga. From the publisher:

Armies march, the clouds roar with fire, and deep in the shadows of the earth, nightmares craft the world's annihilation.

The trillith, born from the dreams of the imprisoned dragon Trilla, have manipulated events in the war since its beginning, crafting the opportunity to fulfill their great desire: to unmake the bonds of the world, freeing themselves from the shackles of corporeal flesh.

Though nations still wage battle on the surface, if the trillith, hidden far beyond the reach of the mightiest army, are not stopped, all will die to their plan. But in Trilla lies hope, for if the heroes can free her from her cursed sleep, she holds the key to restore the Torch of the Burning Sky, whose power will decide the destiny of the war.