Heads up, soldiers: Monday is GameStop, Microsoft and Activision’s big “Modern Warfare 2” launch party.

If you’re around Union Square between the hours of 5pm and 9pm, go check it out.

Details as follows…

When: Monday, November 9. Doors open at 5pm. Game with Fame happens between 7pm and 9pm.

Where: Union Square

What: Fans the chance to play the game before it goes on sale at midnight. During the “Game with Fame,” Philadelphia Phillies pitcher Cole Hamels is going to lead a multiplayer team against a squad led by New York Yankees Nick Swisher and Jerry Hairston.

Who: Besides the baseball players, DJ Jazzy Jeff and DJ Questlove will be there, providing music.