If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
Take to the streets for some urban combat in what was once a quiet residential area. Start with the training mission to learn how the action-packed gameplay works. Do you like fighting with grenades? RPGs? Saws, maybe? Good—you can use these to pick off your enemies, either one by one or in one big bang. Upgrade your weapons, armor, and special abilities when you have the chance!