You may notice that in the image the clouds part not only to shine on Elizabeth during the battle, but to cover the Spanish Armada fleet with dark clouds, as if alluding to this what will happen and who will be the true champion in the battle. In the actual battle with the Spanish Armada, the entire Spanish fleet is destroyed by the turbulent seas, this was seen as God crushing the Spanish through nature and overall shows that God favored Protestant England over Spain Catholic. This battle would demonstrate to the world that God had favored England ruled by Elizabeth by granting her victory in her efforts against her enemies. It could also be said that in the case where the horse crushes the demon while Elizabeth simultaneously saves the Truth, a Protestant ruler fights for truth against evil. It is clearly understood that Protestantism is God's favorite religion and furthermore that Elizabeth is its chosen sovereign