My first Java program was a checkers game using all of the classic rules of the game but with the introduction of two new pieces- the bomb and shield pieces. I used the Princeton StdDraw library to implement the GUI and to handle mouse and keyboard events. I also wrote extensive JUnit tests to handle edge cases.
Players alternate turns, only forward-diagonal movements are allowed with the exception of king pieces who may also move in backwards-diagonal directions. Acceptable movements were determined using calculations.
Bomb pieces destroy themselves upon capturing an opponent's piece as well as all pieces within its radius except shield pieces.