EXCALIBUR 712 Ivan II The Conqueror. Ivan II the Conqueror is Excaliburs popular chess-playing barbarian. Ivan can use his 500-word vocabulary to insult and threaten you in deep, commanding tones or to be your powerful and patient mentor. Are you up to the challenge. The Ivan II challenges beginners to advanced players with an estimated rating of 2000 USCF with 100 levels of play. The strongest level can solve mate-in-8 problems. Comes with magnetic pieces that can be secured in the storage compartment.