«We didn't think much about this at beginning of the mission,» he said, «but now with a stationary rover we can focus on it.» (sciencemag.org)
At the very beginning of Mission 4: Fission, after you exit the helicopter, there will be a Mobile Cover Drone on the right side of the street. (cheatcc.com)
At the very beginning of Mission 4: Fission, after you exit the helicopter, there is a mobile turret on the left side of the road. (cheatcc.com)