Add a new rule, called The Quarry

The Quarry is an entity that contains a publicly tracked quantity of Stone, defaulting to 720; each Engineer also has an amount of Stone which is publicly tracked and which defaults to zero. Every hour the amount of Stone in the Quarry decreases by 1, to a minimum of zero; whenever any Engineer or City Architect would perform any action that would cause the amount of Stone to change they must first update its value to reflect any reduction due to the passage of time.

As a daily action, each Engineer may Mine, which is an atomic action that consists of reducing the quantity of Stone in the Quarry by DICE2 and increasing their own Stone by the same amount.

If there is a rule called The Building, after the line which starts with “W: Wood”, add:

S: Stone. A sturdy but very heavy building material.