Take some perfectly lovely draperies and creep them out with some Creepy Cloth®, available in most Halloween departments. This window was dressed with four grey Creepy Cloths to achieve the desired length and fullness. The cloths were easily attached to the hooks at the tops of the draperies. Grey is a good color as it makes the existing draperies look old, dirty and torn, rather than "decorated."
Of course, adding a dragon to the top of the hunt board, LED lighting inside it, and an unusual lamp with flickering light bulbs add to the effect also.