
Spies provide you with information about other Houses. They are one of your most valuable tools in the game. Spies cost fifty gold each time they are sent, even if no new information is gathered. This amount is deducted without confirmation.
The following information appears on a spy report:

House Name: The name of the House about which this report has been generated.
Lord Name: The full name of the current lord of this House, including his title and nickname.
Liege Granted Titles: If present, this indicates list of all the regions to which this House has titles under its current liege lord. If not present, this House has been granted no titles.
Lord Traits: Possibly the most important line of the spy report. This provides some hints about the lords traits. These are telling of strengths and weaknesses the House may have.
Liege Lord: If present, indicates which House holds the allegiance of this one. If not present, this House has not sworn to any other.
Sworn Houses: Indicates which houses have sworn allegiance to this House. Note that each of the sworn Houses may command vassals of their own which are not included in this list (but are still commanded by this House).
Number of Marriageable Daughters: Indicates the number of marriageable daughters this House has available to help forge alliances.
Treasury: Indicates how much gold this House has in its treasuries at the moment.
Total Incomes: Indicates how much gold this House is collecting in total every year. Note that this figure is a yearly income (the House will collect only half that per turn).
Region Incomes: Indicates how much gold this House if collecting from this region alone. Note that this figure is a yearly income (the House will collect only half that per turn).
This will ask for allegiance from the target House. If you have a daughter of marriageable age, you will be asked if you want to offer her hand as part of the alliance. This is generally a good idea, unless you think she would be of more value in a different alliance. For more information see [Great Houses and Alliances].
Confirms the owner of this region with a hereditary title. This title will increase the loyalty of it's bearer, but cannot be revoked. However, if the bearer loses control of the region, they will also lose the title.
This option will destroy all buildings on a region. It is expensive, but can be used to great advantage when you cannot spend the extra time and take a region by siege. For more information, see [Regions and Buildings].
Burning a region permanently decreases its incomes. It is a drastic measure, and should be used only in certain circumstances. For more information see [Regions and Buildings].
Bribing a castellan to defect to your banner can turn the tide of a battle. It is expensive (often more than the cost of razing and rebuilding) but it allows you to take control of a castle in one turn.
It does not change the allegiance of any armies on the region. This means that if you don't act quickly, you can lose control of the region again. Note that it is impossible to bribe the castellan on the last region owned by any House; a House cannot be obliterated with a bribe.
Since the traits are associated with the head of the House, they will change whenever an heir takes over the throne. This can have drastic in-game effects. For example, ascension of a poor commander can trigger widespread rebellion.
You can use this to your political advantage. By sending assassins against heads of rival houses can force such a regime change. If you are lucky, the heir that ascends to the throne will have more desirable traits.
Marriageable daughters allow a House to forge alliances that would be otherwise beyond their reach. Daughters are politically important, but rare. They are also much easier to assassinate than Kings or Lords. Sending assassins after a daughter of a rival House (particularly if she is the only one) can cripple them politically.
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