Control

Mission 5 takes you through Black Rock Processing in the Maintenance Sector. This is a wordy guide on where to go and how to get there. If you only need the solution to the Oceanview Motel puzzle, that's in the second paragraph below.

Take the service elevator from the Central Executive or any other stop on the sector elevator to the Maintenance Sector. The route to Black Rock Processing is not difficult, but you can't follow the signs to get there initially as the route is blocked. Instead take the door to the turbine and follow the linear path to the light switch. There are some battery puzzles along the way. Use Launch to throw batteries into the sockets, none of the batteries are particularly hidden.

Once you've pulled the light switch three times, entered the Oceanview Motel and rung the bell at reception, you'll be able to access the three motel rooms. The goal with this puzzle is to make the first room configuration identical to the second. Make sure the chair is out, the picture is straight, the radio is on the right and the plant is on the left hand side of the books. Once this is done, you should hear a faint noise and the keys will appear on the desk in the third room. Return to the light switch via the door with the triangle on it. Pull the chord until you reappear in the Maintenance Sector.

Turn around and head into the tunnel until you reach a hole in the floor that you should drop down. From here you can follow the signs for the Atlas Chamber. When you reach a locked door, go up the adjacent stairs and drop down into the office below. After this you will encounter some hiss and a control point you can cleanse. Head up the staircase to speak to Arish, who will send you to find a Black Rock Prism. Black Rock Processing is through the door directly behind Arish.

Be careful, tough enemy up ahead

Interact with the glowing red box and a large hiss (Hiss Distorted) will appear. Hiss Distorted can disappear and reappear, so it is best when it is invisible to stand still ready to fire and quickly evade.

Once the Hiss Distorted is defeated enter Dr. Darling's lab. On the desk at the back is level 5 clearance which you need to grab before continuing on to Black Rock Quarry through the door. Take the elevator down where you will encounter more Hiss. From here keep following the signs for Black Rock Quarry, though you can open up a shortcut if you instead turn left out of the elevator and follow the signs for the NSC Control Room. You'll pass a Control Point as you move toward Black Rock Quarry to claim.

When you get to the double doors after the bridge, be aware that you will have to drop down a broken elevator shaft and encounter Hiss along the way. There's another Control Point at the bottom of the shaft.

Once you enter the quarry, there's more combat. Take the path on the right and stay right until you see some floating bodies. Then you should start to climb the nearby rocks and move forward on the higher level to get to the main quarry excavation site. Once again there will be a lot of Hiss in this area, so use the available cover and launch to your advantage. It is likely that during the combat the batteries scattered around the area will move, but there are plenty here so even if some become hard to reach keep looking around for alternatives. Use higher ground to spot them if needed. Attach the batteries to the points on the rock face and activate the explosives to get some Black Rock Prism.

Once you have the prism get to high ground and look for the metal staircase. Exit the area and fast travel to Central Executive to speak to Marshall and end the mission.