Cyran avengers remember where they were and what they were doing on the Day of Mourning—the day their nation was destroyed. A few bore witness to the cataclysm firsthand and were driven from their homeland by rolling clouds of dead-gray mist. Others were fighting battles on foreign soil that day and escaped the devastation. They have spent the past four years piecing together their shattered lives and coming to grips with the loss of friends and family. Now, these vindictive survivors seek to uncover the cause of the cataclysm and avenge their people against the architects of the Mournland. Cyran avengers also harbor lingering animosity toward those who threatened or betrayed Cyre during the Last War, and they struggle daily to harness or put aside this hatred. They refuse to believe that Cyre had any hand in its own destruction or that the Cyran people should be unduly punished while the remaining Five Nations enjoy the peace afforded by the Treaty of Thronehold.
Source: Five Nations
A number of Cyrans hold tangible forces responsible for the Mourning, the most common scapegoat being one or more of the nations that opposed and ravaged Cyre during the Last War. A few of these patriots, such as the members of Prince Oargev’s Covenant of the Gray Mist, channel their wrath into investigating the Mournland’s birth. The Covenant is withholding final judgment, and revenge, until that mystery is unraveled. In the meantime, these patriots work to cleanse the land of its twisted inhabitants.
Others walk darker roads. Some Cyran vigilantes punish anyone who once acted against Cyre or currently acts against displaced Cyrans. They avidly seek justice for past wrongs, real or imagined, but even so usually require some proof of guilt. Other displaced warriors—such as Dannel’s Wrath in Stormreach on Xen’drik—organize not only to protect Cyrans, but also to seize a new Cyran homeland. They plan to do so by force if necessary.
Still other Cyrans are outright outlaws and killers who need no proof or approval to mete out “justice.” The Mourning Dawn, a loose network of Cyran terrorists, operates across Khorvaire, dedicated to making everyone on a long roll of Cyre’s enemies pay. The Dawn places House Cannith at or near the top of its list.
Source: Eberron Campaign Guide