The Rat has been seeking revenge since your last encounter. His Army has landed on our coast and will attack soon. You must defend the castle at all cost.
Starting goods with Pitch are useless because you can't use it for defense or sell.
Lots of restrictions in market which is good for forcing weapon and stone production.
Plenty of walls are quite safe to defend.
You can add more challenge to the map by changing the castle landscape from grasslands into high mountains which make farming difficult. But please give buy sell access to iron because the iron mine close to castle makes it redundant except for producing maceman