The quori are far more unified than their counterparts in the Lords of Dust or the Order of the Emerald Claw. Should the quori fail in their task, il-Lashtavar and all of its children will be destroyed. The existence of their entire species is on the line, and as a result, the quori don't turn on one another lightly.
Still, some question the methods and authority of the Devourer of Dreams. Riedra has given those nightmare lords a structure to build their own followings.
Lady Sharadhuna of the Thousand Eyes is the Devourer's greatest rival. Although Sharadhuna believes control of humanity should anchor Dal Quor and prevent the turn of the age, she thinks that Sarlona is sufficient to accomplish this goal. Sharadhuna believes that the Devourer is pressing for continued expansion not on the orders of il-Lashtavar, but because he draws power from the pacified populace. If Sharadhuna is correct, the Devourer actually seeks to replace il-Lashtavar, assuming its place as the driving force of Dal Quor. Sharadhuna believes that the quori need be concerned only with fully securing Sarlona, including Adar, Syrkarn, and the Tundra. She resents the unquestioned authority held by the agents of the Dreaming Dark and believes that the Thousand Eyes is performing the most crucial work of the age. Sharadhuna is gaining supporters, and she hopes to find a way to supplant the Devourer as the voice of il-Lashtavar. Still, she has no idea what such a transformation could require.
A third faction is led by Lord Zoratesh, the commander of the Harmonious Shield. He has no patience for the slow manipulation of the Dreaming Dark, and he wants to launch an invasion of Khorvaire. In such a scenario, psionic teleportation circles would be used to launch sudden and decisive strikes against the capitals of Khorvaire, seeking to eliminate nobles, dragonmarked barons, and other threats. Both the Devourer and Sharadhuna believe that this event would be disastrous, providing a common enemy to unite the people of Khorvaire, destabilizing Riedra, and risking the ire of the dragons, the Lords of Dust, and other conspiracies currently watching from the shadows. Zoratesh currently lacks the support required to pursue war, but if an Inspired invasion of Khorvaire were to happen, Zoratesh would be the one to lead it.
Getting the PCs Involved: Lady Sharadhuna can be an unlikely ally for the PCs. When the characters are captured by the Thousand Eyes, to their surprise, they are not executed. Instead, Sharadhuna provides them with information they need to upset some of the plans of the Dreaming Dark. Using the PCs as her catspaws, Sharadhuna can embarrass the Devourer and increase her support, possibly even supplanting the Devourer. If Sharadhuna assumes power, she focuses her efforts on Sarlona, and Khorvaire becomes a safer place for it. Adar, on the other hand, becomes less so. Although she might help PCs fight the Dreaming Dark, Sharadhuna does nothing that could endanger Riedra.
A war between Khorvaire and Riedra would be a devastating conflict, with the widespread magic of Khorvaire and the dragonmarked houses matched against the devastating psionic power of the Inspired and their willingness to sacrifice their fanatical troops. Even if the Riedrans won the conflict, the Khorvairians wouldn't accept defeat easily. The unity of Riedra succeeds because the people believe that the Inspired are saviors, not conquerors. However, a band of adventurers struggling to raise a resistance movement in the wake of a Riedran conquest can form the basis for an interesting campaign, whether it's set in Khorvaire, Syrkarn, or the Tashana Tundra.