I started off with a resized and reshaped cube, 8 cylinders, 3 flattened spheres,4 cones plus a cylinder shaped with the bend tool.
step 2 of 2
I drew an oblong on the roof and used the area pull tool. I resized a cube for the drawbridge, several torus shapes for the chain and added a base using a resized and reshaped cube. Then I added a reflected gel shader finish with z-brush and rendered it.