Russian Rybka Aquarium 4.0

Rybka 4.1 engine - World Computer Chess champion and rating lists leader. Rybka 4.1 can be also used in Fritz and other chess programs. With a copy of Deep Rybka Aquarium 2011 you will also get a bonus of Openings Encylopedia 2011, which includes rich theoretical material on all the openings, more than 8000 annotations from GM Kalinin and 500 000 expert evaluations expert evaluations to key opening positions, which were verified and corrected by Rybka and 40 million of evaluations by Rybka engine. There's a powerful search system as well.