Cevat Yerli is a prominent figure in the history of Crytek. He and his team launched an impressive demo The X-Isle: Dinosaur Island in 2001. Later this project turned into a FarCry. The demo was intensely technical: sporting a then-unseen level of detail and draw distance. Later he moved from beind solely a Technical and Creative Director and started working as a CEO, helping R&D and handling the management.
If you ask any engine developer, who worked on complicated rendering problems, about Cevat Yerli you’re almost certainly hear some good words. His tech really was (and in many cases still is) ahead of his time. It was used in a countless number of games and partially powers some of the most powerful engines today (like Lumberyard and Cryengine). So seeing him go away is just a bit sad.