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- Bronze: 13
- Silver: 9
- Gold: 7
5 Portal Strategy
- Proceed forward and shoot a blue portal onto the ceiling on either side of the room.
- Shoot an orange portal at your feet.
- While falling, shoot a blue portal at the wall directly above the entry doorway.
- Duck and shoot a blue portal through the hole-aim to the left and high up on the wall above the black row of blocks.
- Bring the cube with you to the lower level and set it on a button.
- Drop through the orange portal on the floor and land on the shallow ledge.
- After the lightning stops, run forward and take a right into the safe area.
- Shoot an orange portal through the hole then go back past the lightning and jump across to the blue portal.
- Climb the black blocks then carefully walk along the right wall on the white part of the laser floor.
- Crouch and grab the cube then bring it with you to the next area.
- Hold the cube and with your back to the door you can use it to press the button down. Once you get yourself in the doorway it won't close so you can grab the cube and pivot 180 degrees then drop down still holding it thus using no more portals.
- Set the cube on the remaining button and proceed to the exit.