👑 Medieval Kingdom Builder: River Valley Dominion with Castle, Port, Army and Diplomacy

Rule a 3D river-valley kingdom from a castle lookout: build houses, farms, mills, barracks, a castle, a market, a port and walls while gold, timber, stone, food and population follow logistic growth, harvest seasons, wind power and a price-depth market. A harbour of trade cogs obeys Archimedes' law (cargo limited by water depth), a garrison with drill sets your defence rating, and three neighbouring realms trade or make peace as their relations drift. Ten numerical checks and six royal decrees.