Order only. Attach to a target unit you control. Action: When your capital is dealt damage, deal 2 damage to target unit in any corresponding zone.
Let's have an example:
I have a unit equipped with Asrai in Kingdom, a Spider Riders attacks my capital from quest and gives 2 damage. Now with the ability of the Asrai, the "corresponding zone" it's Kingdom, where Asrai is equipped, or the Quest of my enemy, where the damage where dealt?