Deep Rybka 4 UCI (download)Deep Rybka 4: The Worlds Strongest Chess Engine Deep Rybka 4 UCI is the world champion of chess engines with a rating of 3250+ points ELO. The main developer of the program international master Vasik Rajlich has inserted the algorithms of positional estimation into it which are as close to the chess players style of thinking as possible. Rybka is a UCI chess engine, which means that you can use it with almost any modern chess user interface such as