I noticed while looking for pictures for The Return of the King that the scene in the book where Eowyn slays the Witch King has inspired some rather good and iconic art. This picture in particular is interesting because it self-consciously mimics an old style of representation. I think the key contrast in to emphasize when depicting this scene is the brightness of Eowyn's hair versus the darkness of the Witch King. This picture does a wonderful job of that, with Ewoyn the subject of celestial light while the Witch King almost recedes into the darkness of the clouds.