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Question about The Cards Spy - If a Spy played by my game partner fails because of my Great Wall or my Watch Tower, do I nevertheless have to show him the cards in my hand, only that he can’t steal any from me?

Answer

No. A failed Spy played by your game partner has no effect on you.

Note: Great Wall and Watch Tower belong to the theme sets "Science & Progress" and "Knigths & Merchants", which are part of the Catan Card Game – Expansion Set.