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Question about General Questions Center Cards - What are Center Cards?

Answer

What most Center Cards have in common is that once they are placed in a principality, you can't move them until the game ends; at best, you can place other Center Cards on top of them (Citadels and cities on settlements, and Metropolises on cities). The Public Feeling in its capacity as an abstract Counting Card is an exception to this: it can be moved at any time during the game if a player wants to make different use of the building site it is placed on.

Note: The Citadels belong to the theme set "Wizards & Dragons", which is part of the Catan Card Game – Expansion Set, the Public Feeling belongs to the Artisans & Benefactors Expansion Set.