From the back cover:

Alexander, the Great King, will visit the Oracle! Apollo, God of Clairvoyance, help us! Why is this bad? Well, as high priest of the oracle, it is your craft to tell the future. No issue there. But it will be hard to tell only that part of the future that the King wants to hear. Because if your prediction displeases His Majesty, your own future may not lok to bright...

In Oraklos, players predict the future by throwing many coloured dice into the table. By gazing at the resulting pattern, they simultaneously try to find elements of the prediction Alexander wants to hear. The fastest sweettalking soothsayer wins the game.