Yiğit Köroğlu makes designs and illustrations for various films, games and books. Wizards of the Coast, Titmouse Inc., Bandai Namco, Bushiroad, Paizo are companies he mainly works with. He also makes drawings for many independent individuals and organizations. Colored illustrations to be printed inside "The Devil's War" and front/back cover drawings belong to Yiğit Köroğlu.

Utku Ozden was born in Antalya, Turkey in 1983. He graduated from Bilkent University Graphic Design. He still works successfully as an illustrator and designer in many projects. Black-and-white illustrations that will be printed in "The Devil's War", video drawings at the beginning of each chapter and the illustrations used in the promotional video belong to Utku Özden.