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- Bronze: 16
- Silver: 12
- Gold: 10
9-10 Portal Strategy
- Proceed forward and shoot a blue portal on the wall directly ahead of the elevator.
- Shoot an orange portal on the wall across the room from the doorway, near the disintegration barrier.
- Move straight forward and wait in the small alcove until the crusher comes all the way down.
- Hop on top of the crusher then ride until it is possible to drop over the wall to the other side.
- Shoot a blue portal through the hole, slightly above floor level, then shoot an orange portal under your feet.
- Once the crusher has fully descended on the orange portal side, jump through the blue portal and you will again be on top of the crusher and able to ride it to the top of the wall.
- Drop down, go through the orange portal, and ride the last crusher up. Near the top, shoot an orange portal through the hole, a blue portal on the wall above, and quickly go through the blue portal.
- Wait near the moving piston until it has just past the wall, then quickly jump/run forward and try to make a u-turn at the edge of the small portal-immune wall. Then shoot a blue portal on the wall ahead and go through. This may take a few tries.
- Just as the first piston could be passed without shooting a portal, the third can as well. Skipping both pistons one and three will mean finishing with 9 portals, whereas skipping only the first (which is by far the easiest way to go) will allow finishing with 10 portals- the gold requirement.
- After having skipped or used another blue portal to pass the third piston, the last one is passed by running forward, shooting an orange portal against the wall ahead, shooting a blue portal through the hole in the glass, then proceeding through the blue portal to the exit.
- A slightly faster method for completing steps 6-7 (and one that is less likely a glitch) is to shoot a blue portal on the wall as close to the corner of the glass as possible. Then once the crusher has passed the blue portal, jump through the orange and carefully land on the bottom edge of the glass. From there, shoot an orange portal through the hole, proceed through the blue, then follow step 8 as normally.