Copper is your first line of defence. Maintain your castle's copper at the maximum your Keep can hold.
A keep full of copper means you have a higher chance of catching spies:
In order to successfully spy on your castle, the player spying your castle has to send more copper with their spy than there is in your castle's keep.
If this is the case, the player will have a spy report on your castle without you knowing.
If the player's spy is sent with less copper than there is in your castle's keep, you will catch the spy. It costs you copper equal to the amount sent with the spy.
So maximizing the level of copper in your keep protects you from being spied on.
Replenish your copper store as fast as you can.
Spies almost always imply intent to attack. So if you catch a spy, be on the alert, ask for support if you need it and don't run tavern missions that use defensive troops.
😎ATTENTION!! 😎
Do not forget to replenish copper to avoid undetected spies
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Check your spy reports regularly - the only way to see if you've caught a spy
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