Add a new bullet point to the bullet point list of workplaces in the rule “Workplaces” with the following text:

Trading Post (Merchant): Announce the names of all Merchants in the blog entry announcing this Day of Observance as Active Merchants until the next Day of Observance.

Add a new dynastic rule “Marketplaces” with the following text:

Any Townsperson who was announced as Active Merchants in the blog entry announcing the most recent Day of Observance is considered an “Active Merchant” until the next Day of Observance. Any Active Merchant may post an Offer as a comment to that blog entry. He is considered to be the Seller of that Offer. An Offer must contain a list of one or more non-Human, non-Plague things the Seller offers and a list of one or more non-Human, non-Plague things the Seller demands.

For an Offer to be valid the following conditions have all to be true:
- It has not been accepted.
- The Seller has all the Things offered in his Home.
- It must be a comment in the most recent blog entry announcing a Day of Observance.
- The Seller has not made a comment in the same blog entry announcing that he retracts that Offer.

Any Active Merchant who has the Things demanded in a valid Offer can accept it by posting a comment to that same blog entry announcing that he accepts it. He then has to immediatly remove the Things demanded in the Offer from his own Home and add them to the Home of the Seller of the Offer. He then has to immediatly remove the Things offered in the Offer from the Seller and add them to his own Home.