CODERULER is derived from 2004 ACM International Collegiate Programming Competition (see IBM reference), which is the latest fantasy game simulator challenge for IBM AlphaWorks. This game has a simple setting: You are the ruler of our medieval kingdom. Your farmers and knights depends on your wise strategic thinking, flexible strain ability and people's Java programming skills to survive, develop and prosper. As a game participant, your goal is to write Java code that simulates this ruler. The game simulator allows your rulers to deal with six opposing rulers (or built-in sample rulers) and determine the winner. From you to: From the easiest way to test-based mechanical rulers to the most complicated, CODERULERS is provided by the statistical game theoretical model. Just like in the real world, the most complex strategy and complex coding may not guarantee victory. In fact, some champion rulers use the easiest, but the most exciting guerrillas. If the strategic design and Java development are your favorite, then you should try CODERULER. Figure 1. CODERULER in the run