5. Left 4 Dead
Would you trust your friends to have your back during a zombie outbreak, or would you go at it alone? This is the issue Left 4 Dead raises. Essentially- team work is essential. If there are hordes of zombies, your chances of surviving by going at it alone are virtually zero. So pick who you can trust, pick up the closest baseball bat and go nuts!
4. Disaster Report
Natural disasters are always one thing that keeps us on the edge of our toes- this game put us in that scenario for real. You have to dodge and navigate around fallen buildings as well as the odd earthquake which is thrown in for good measure. In addition to your HP you also had an energy gauge which depleted when doing strenuous tasks such as running or climbing- this could be restored with drinking tap or bottled water, a really nice touch to the gameplay. The hero wasn't some beefy action hero either- he was a photographer- so naturally a part of the story is finding out what is causing these disasters.