How to Succeed in War Without Really Trying
Common Knowledge: Jewel of Galifar and rightful heir to the throne, poor Cyre has probably fared the worst over the war so far. With Karrnath sacking its capital roughly 15 years ago, the rebuilding efforts continue, causing Cyre to take a mostly passive role in the war lately. However, they've been more than happy to direct some money from the Mint of the Five Nations towards mercenaries that are willing to fight for the Cyran cause.
Still, they know that they're fighting for their just birthright, and that means they're unlikely to stay on the backfoot for long.
(Think Italy, only they all more or less get along and have a massive chip on their shoulder towards the other nations.)
Allies: While technically the Dragonmarked Houses have an oath of neutrality in the conflict, The Twelve sees Cyre (and their massive stacks of gold) as first client among equals.
As Mror Holds continued independence is a source of endless frustration to Karraath, Cyre is more than happy to give them reasonable military aid. The Mror Holds, of course, return the favor whenever possible.
Enemies: Karrnath's sacking of Metrol still burns in the mind of every red blooded Cyran man.
To a lesser degree, Cyre resents the other nations for starting the war and trying to deprive them of their birthright.
The True Danger: if Cyre ever regains the throne through force of arms, it would not hesitate to exact revenge on all the nations that stole Cyre's birthright, causing another civil war to spring up and kill any remaining chances for a lasting peace.