Moonfall — John Kelly

In the summer of 2091, Terry McGill tries to penetrate the mystery of a new game in town and meets a beautiful green-eyed woman who changes his life. When Terry and his friends separate to seek their fates, he returns to the mysterious Warmark and discovers that it's far more than a game. In adventures ranging from the mountains of the Kazahk to the sands of the Sahara, he fights, learns, grows and discovers his own strengths until the electronic intelligence controlling the simulation tries to kill him for real. Leaving simulations behind, he seeks to catch up with his friends in their progress toward becoming star colonists by working and learning on the moon. His one-time nemesis becomes an ally and helps him save the moon base when an errant iceball strikes. Terry is feted as a hero on earth, but time is running short for him to get into the star colony project. When he returns to the moon he's mouse-trapped by the biggest plot of all, one which threatens his life, the star colony mission and all of Earth.