The Invisible Knight — Ann A. Guerra; Daniel Guerra

Witnesses who were present at the scene of the events told that the warrior manifested himself fast as an eagle, and almost with supernatural powers. He appeared and disappeared like a bolt of lightning on the battlefield. Because of his great help they obtained the victory. The knight had more than skills and dexterity. Besides being a good warrior, he was the possessor of a great wisdom and technology far superior to the one existing on Earth at that time. He belonged to an ancient civilization who had originated on planet Earth, but after a universal war when half of the planet was destroyed, many earthlings mounted their spaceships, and went in search of other planets where to live.