Video Description:

Once you begin progressing through the mission with two Marines, this is the point where you need to keep them alive. Progress forward aggressively taking out the enemies as quickly and efficiently as possible. You'll eventually meet up with another four soldiers who ALSO need keeping alive. Continue to be aggressive and once you make it up the hill, the marines will position themselves on turrets behind sandbags. Keep control of the enemy flow as they try to make their way up the hill. Once clear of this section and all SIX of the Marines are alive: Achievement Unlocked!