Fantasy Flight Games have posted a Gears of War strategy article examining the various reaction abilities available in the game. From their website:
With the recent release of Gears of War™: The Board Game, hobby game enthusiasts across the world are quickly learning (in some cases, the hard way) the importance of planning, communication, and solidarity in battle. True to the tense action of the popular video game series, Corey Konieczka’s clever design ensures that players who venture off alone to gun down stray Drones quickly find themselves cut off and overwhelmed. How can you and your team avoid this fate?