Object: reduce your opponent to two or less pieces. Euclid uses the coordination method of capture from Ultima.
 
A King moves like a Chess Queen, sliding any number of squares in any direction. A King can not make any captures when it moves nor can a King be captured.
 
A Man moves like a Rook, sliding any number of squares in any orthogonal direction. When it finishes a move, it captures any enemy Man on an intersection of the orthogonal lines that pass through the Man and through the friendly King. Imagine the rectangle formed on the board by the Man and the King of the same side; the captured pieces are on the rectangle's other two corners. It can therefore capture two at once.