Tic Tac Lego
Greetings, Earthlings! I am Xyzygy and I hereby challenge you to a game of skill. If I defeat you, I will send my fleet to conquor your pitiful world. However, in the unlikely event you are fortunate enough to vanquish me, I will leave your petty planet alone...for now.
Just click on the sector of space you wish to claim. If I form I blockade of three of my troops in a straight line, I win. If you get three of your troops in a line, you win.
You will need a Java-enabled web browser in order to defend your planet.