This guide is for the end boss. First i would recommend you choose Ross, he can take alot more damage than the other two characters. This fight is more annoying than tough, the boss has a pattern which you will soon learn. He will appear on one side of the room go through the door and re-appear on the opposite side of the room! Stay on the back wall, if he appears on the right shoot (there are several holes in the debris to aim through depending on where you stand), if he appears on the left throw a grenade, he usually positions himself near the fireplace so aim here. Several enemy soldiers will enter the area during this time, they should not give you too many problems, most of them drop grenades when killed, so you can top up on ammo if you need to.