Control - Find the Black Rock Prism by exploring the Black Rock Quarry

How to find a Black Rock Prism in the quarry.

You've made your way through the Turbine Room in Control and, surprisingly, the Oceanview Motel again to reach Black Rock Processing.

Getting a Black Rock Prism, however, is going to be surprisingly harder than it looks. You're going to end up climbing down into the Black Rock Quarry that is, somehow, beneath the Federal Bureau of Control.

I think we can all agree that the Oldest House is not your regular office building.

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Need more help in your quest through the Oldest House? Then check out our Control walkthrough hub, with links to all our Control guides.

Find a Black Rock Prism

It's time to explore Black Rock Processing, head through the door on the right-hand side of the room and keep following the corridor until you reach Black Rock Processing.

Head down the right-hand side of the corridor and through the double doors at the end.

Upon entering this room, Jesse's psychic friend will illuminate a container for Black Rock Prisms. Go and check a look.

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Sadly, you'll discover that all the prisms have shattered. Things get worse as you'll be attacked by a Hiss Distorted.

Hiss Distorted have the ability to turn invisible. The best way to attack this monster is to use your Launch power to ready a projectile and then throw it at the Hiss Distorted when it reappears. A couple of hits and it will die.

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Yup - that's a monster.

Collectables to be found:

  • Case Files - Altered Items - Swan Boat Procedures
    • (In the alcove to the left when you first enter Black Rock Processing.)
  • Research & Records - Hiss Research - Hiss Distorted
    • (Receive upon killing a Hiss Distorted.)
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The location of the collectable - Swan Boat Procedures.

Search Dr. Darling's Black Rock Lab

Killing the Hiss Distorted will allow you to access Dr. Darling's Black Rock Lab in the left-hand side of the room. The door tells you to wear a protective coat, but I'm sure you'll be fine.

When you enter Darling's Black Rock Lab, there will already by a Darling Presentation running. You'll learn that the Bureau mines its Black Rock from a quarry - if you want a Black Rock Prism you better head there.

Go to the desk where the presentation is playing and take the Clearance Level 5 key you find on the desk.

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The Clearance key is next to the television.

Collectables to be found:

  • Multimedia - Darling Presentation - Black Rock
    • (Receive upon entering the Dr. Darling's Black Rock Lab.)
  • Research & Records - Research - Black Rock
    • (On the floor in Dr. Darling's Black Rock Lab.)
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The location of the collectable - Black Rock.

Find the Black Rock Quarry

Before you leave Dr. Darling's Black Rock Lab, head upstairs and open the chest you'll find there. Once you've done that head through the door to the Black Rock Quarry with your fancy new Clearance Level 5 key.

Go through the door and take the lift to the next floor.

Follow the corridor and you'll find yourself on a set of walkways high above the NSC Energy Converters. Take out the enemy Hiss that will attack you as you travel through this room and take a quick detour to the left to open a chest, which is through the door to the left.

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Go through the door for the Black Rock Quarry and head up the stairs. Ignoring the lift, head to the right and through the door. You'll emerge on the higher levels surrounding the NSC Power Plant and here's a Control Point for you to cleanse on the left.

Follow the walkways to across the Power Plant and reach the Black Rock Quarry, taking out the Hiss you cross paths with. Here will also be another chest for you to open.

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When you reach the other side of the Power Plant, head right until you reach the Clearance Level 5 door.

Beyond this door you'll find a new elevator and a shelter containing a chest.

Sadly, the lift doesn't seem to be working today, so, instead, you're going to have to climb your way down the shaft.

To start this drop down to the lower level next to the elevator where you can see the crates. From here you can easily go down floor to floor, level by level, by jumping down on walkways beneath you or onto pipes.

As you descend, there will be a couple of Hiss Charged you to take out and don't be surprised if you take some fall damage as well.

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Jump from pipe to walkway, killing the Hiss Charged as you go.

When you finally reach the bottom of the elevator, take out the Hiss waiting for and cleanse the Control Point. From now on, the elevator will work perfectly.

Make your way into the Black Rock Quarry and kill the Hiss that attack you.

After killing the Hiss, take the right-hand passageway. Be careful when you take this path, because at the end you'll find another rubble creature from the Astral Plane.

You can either begin climbing the stairs to avoid it or run past it for the chance to find a collectable and open a chest. These items are guarded by a horde of corrupted mine workers, but they are trapped behind a pile of stone allowing you to easily kill them.

When you're ready, go up the stairs and then climb up the stone blocks. You'll find yourself standing next to a set of floating stones. It's time to do some platforming - jump from one stone to another to reach the other side.

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Once you've on the other side, you can take a quick detour to the left, climb up to the next level and come across a chest hidden in an alcove in the rock.

Head straight on to enter the Black Rock Quarry and you'll find yourself beneath a surprisingly starry sky.

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Drop down to the quarry floor and head to the staircase on the left. Opening the door you find at the top will create a useful little shortcut if you need it later on.

Collectables to be found:

  • Research & Records - Research - NSC
    • (On the computer bank on the upper floor of the NSC Power Plant.)
  • Case Files - Altered Items - Fan Supplement
    • (Climb over the fans in the NSC Power Plant room just before the door to the elevator that takes you to the Black Rock Quarry.)
  • Correspondence - Non-Official - Quarry Equipment Order
    • (On a block of stone in the right-hand passage to the Black Rock Quarry.)
  • Correspondence - Non-Official - Quarry Worker Incident
    • (In the Black Rock Quarry after running past the Astral Plane creature, take a right, kill the creatures behind the stone blocks and then climb over the blocks to find this on the other side.)
  • Correspondence - Official - No Smoking Reminder
    • (In the main part of the Black Rock Quarry, then the stairs near the shortcut door.)
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The locations of collectables - NSC, Fan Supplement, Quarry Equipment Order, Quarry Worker Incident and No Smoking Reminder.

Activate the explosives to excavate the Black Rock Prism

Now head to the centre of the quarry and take out the Hiss occupants. Be prepared for this battle, because a range of different Hiss enemies will attack you, including two Hiss Warped backed up by a Hiss Cluster.

Remember to take out the Hiss Cluster as soon as it appears, because they can heal other Hiss enemies. You'll also have to fight off some Hiss Charged, so avoid getting stuck in a corner during this fight.

When the Hiss have been defeated, it's time to start putting electricity boxes onto sockets.

The three sockets are directly opposite where you fight the Hiss forces on the wall and you can easily find electricity boxes throughout the quarry. Use your Launch powers to place the electricity boxes on the sockets.

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Ready to explode.

When the electricity boxes are placed, run back to the computer bank in the centre of the quarry and press the red button to blow up the wall.

Collectables to be found:

  • Research & Records - Reports - Quarry Incident
    • (On the computer bank in the middle of the Black Stone Quarry.)
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The location of collectable - Quarry Incident.

Collect the Black Rock Prism from the excavated seam

Run up to your exploded wall and collect a Black Rock Prism.

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It’s time to journey into the mysterious Federal Bureau of Control. Our Control walkthrough can help you through the storyline missions, including Welcome to the Oldest House, Unknown Caller, Directorial Override, Old Boy’s Club, Threshold, My Brother's Keeper, The Face of the Enemy, Finnish Tango, Polaris and Take Control. You can also learn new supernatural powers by completing A Merry Chase, A Good Defence and A Captive Audience. We also have guides on upgrading the Service Weapon, your Abilities, how to use Weapon and Personal Mods, how to unlock every outfit and the solution to the Roulette Wheel puzzle.


Speak with Marshall

With the Black Rock Prism, you can now head back to Marshall.

Monsters from the Astral Plane will now appear in the quarry, so climb up to different levels to avoid them or simply run past them. You can take the shortcut you opened up previously, by heading up the stairs and going through the door.

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Avoid the monsters from the Astral Plane.

There will be more Astral Plane monsters between you and the elevator. Quickly run past them. Now you can either fast travel via the Control Point back to Central Executive or you can take the long road back through the Maintenance Sector.

Either way Marshall will be standing near the Control Point - tell her about what you've been up to.

Collectables to be found:

  • Hotline - Board - Astral Constructs
    • (Receive after completing Threshold)

Now it's time to find Dylan in My Brother's Keeper.

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Lottie Lynn

Lottie Lynn

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