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Part 31
Portal

Part 31

Complete walkthrough for Part 31 of Portal, covering Advanced Test Chambers 16 and 17, including turret puzzles and companion sphere challenges.

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Complete walkthrough for Part 31 of Portal, covering Advanced Test Chambers 16 and 17, including turret puzzles and companion sphere challenges.

Walkthrough
  1. 1
    Stand at the bottom left of the '+' shape formed by the dividing walls. Shoot one portal where the energy ball hits the wall and the other on the perpendicular wall.
  2. 2
    Go to the bottom right of the '+' and shoot one portal where the energy ball will hit the wall, and the other on the wall perpendicular to it (near the door with the piston).
  3. 3
    After the energy ball exits the second portal, rush to the upper right of the '+'. Shoot one portal where the energy ball will hit the wall and the other at the orange light above the receptacle.
  4. 4
    Ride the piston up, go through the hallway. Place one portal on the white ground right next to the partition.
  5. 5
    Go through the door in the corner and shoot the other portal at the ceiling in the small inlet there (in a "U" shape, near the back, not directly above the black wall).
  6. 6
    Run back and fall through the portal near the wall.
  7. 7
    While falling, place the portal you just came out of (the one on the ceiling) where you will land.
  8. 8
    While flying up through the portal near the wall, move the analog stick to land on top of the partition. Fall to the other side.
  9. 9
    Run to the door and shoot a portal at the wall perpendicular to the far wall (not the absolute farthest one parallel to you, but the one at 90 degrees to you and the far wall).
  10. 10
    Shoot the other portal to the right of the doorway. Crouch down and inch into the doorway. When you can shoot, shoot a portal at the wall perpendicular to the far wall using the portal you placed on the previous perpendicular wall.
  11. 11
    You will be pushed out of the portal to the safe ground behind you. Inch back to the portal and shoot another portal at the white wall in the far room.
  12. 12
    Get out of crouch and run through the portal. Ride the closest piston up to the top.
  13. 13
    Turn and face out of the doorway of the small room to find another small room caddy-corner from yourself on the far side of the room. Shoot a portal at the ceiling of that room.
  14. 14
    Push the button in this room, then run over to the ledge with the piston under it. Jump off and shoot the portal opposite the one in the far room at the ground where you would land.
  15. 15
    After you land, quickly go over and push the button. Run over to the ledge near you (that also has a piston under it) and turn right to see a pushed out concrete slab. Put one portal there and the other on the ground where the energy ball is hitting.
  16. 16
    After it lands in the receptacle, ride the newly lowered piston up and enter the chamberlock.

Advanced Test Chamber 16 (AC16)

  1. Run out of the chamberlock and into the door on the left. Shoot one portal at the wall above the box and another at the wall. Go through to land on the box.
  2. Crouch under the doorway and drop through. Quickly run to the doorway to the right to get out of the line of fire (from a turret).
  3. Pop out of the doorway and shoot a portal down the hallway. Shoot the other portal near the door and run through.
  4. Turn left and follow it down. Shoot one portal at the ground (not at your feet). Pop out into the hallway and very quickly shoot a portal at the ceiling down the hall.
  5. Grab a box (for protection) and drop down into the portal.
  6. Quickly run through the door to the right with the box in the way of the fire coming from the turret. Get out of the way behind them.
  7. Get behind the far turret (the one across from the left doorway) and drop the box in front of it.
  8. Look into the right doorway and shoot a portal at the far wall. Shoot the other at the wall near you and go through.
  9. Grab a box in here and return to play it on top of the other box to totally block off the view of the turret.
  10. Grab another box from the room. Go into the left room and quickly place the box on the button.
  11. Retreat back and aim through the doorway. Shoot a portal at the wall through the doorway.
  12. Grab the box and retreat to the portal in the wall behind the turrets. Crouch down and run through.
  13. Place the box in front of the grate near you to block the fire from the turret.
  14. Shoot a portal at the wall behind the turret, then go through, leaving the box.
  15. Look through the grate to see a turret and another doorway. Aim your portal through there and shoot it at the wall there.
  16. Re-enter the portal near you and head into the chamberlock.

Advanced Test Chamber 17 (AC17)

  1. Run forward and grab the companion sphere. Bring it into the next room and use it to climb up to the next ledge by placing it in the corner the ledge makes.
  2. Once on the ledge, turn around and grab the sphere. Use it to get on top of the next ledge by placing it in the corner. Turn around and pick it up.
  3. Place one portal where the energy ball hits the wall and grab the companion sphere.
  4. After the energy ball hits the wall, hold the sphere in front of you and run down the hall. Once at the end of the hall, turn and face the next hallway.
  5. When a new energy ball is shot from the dispenser, carry the sphere in front of you and run down the hall and the stairs at the end.
  6. Enter the larger room and jump down. Enter the room without the slanted pieces next to it.
  7. In here, hold the sphere in front of you as you approach the dispenser. You have to make the energy ball bounce over the barrier and into the receptacle.
  8. The easiest way to do this is to stand where you are in front of the receptacle but a few steps backwards (from the dispenser). If you're in the right place, your sphere will be right in front of the receptacle, but on the other side.
  9. Let the ball bounce off of the top right portion of your sphere. Keep trying until you get it.

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