The haunted tower and it's roof are assembled by bending the main tower on all the fold lines as shown, including the fold lines at the base of the tower point. The tabs for the tower peak must be bent at right angles so they will fit under the non tabbed sections of the tower top.
Begin by gluing the tower sides together, and gluing the tower roof to its tab. While the tower roof is drying, apply glue to the tabs of the point of the tower, and fold back all four sections of the top of the tower so it meets at a point centered above the main building. You may need to hold it gently while it dries. When the tower building is dry, apply glue to the underside of the tower roof and fit it in place on top of the tower.
The tower building can be used against any of the other buildings or it can be used as a second story on the larger mansard roof building.