Also, the potential shortcut of flinging to the exit (see portals challenge, silver method), as in chamber 14, is prevented. The final room has only the ceilings in the side rooms usable.

The transition hallwayвЂ™s platforms move significantly faster, but the same method can be used, just with more accurate timing. So place a portal there, and another where the pellet hits the adjacent wall (not the angled platform), and watch it bounce its way to the receiver. Trace a path backwards from the receiver, bouncing off the platforms as a pellet would, and you will discover that the pellet needs to be coming straight out of the wall next to the three angled platforms (on that same wall). Notice the additional angled platforms, preventing the normal method. Now that you are with the pellet launcher and receiver, fling yourself over to the other side as normal. As you fall through, put another blue portal under you to fly back through to the main room and maneuver over to the next section. Another method which is more guaranteed is to, after placing the orange portal similarly, place a blue portal on the ceiling of the side room above the low floor. If you jump off the ledge and into the portal, pressing the necessary direction, you can manage to come up with just enough momentum to walk through the field into the next section. Take note of which direction the field is. Now place a blue portal on the floor below you. Place a blue portal on or below the camera, and come through to land on the side roomвЂ™s ledge. Place an orange portal sideways as close to the emancipation field as possible. Room 3 has no portalable walls in the main room, and no staircase in the side room. The pellet moves a little slower, which requires you to place the next portals by the time the pellet hits the wall the first time, or else it will disappear and you will have to start this room again. Room 2 has an additional forcefield, requiring a 6-portal combination. You can do this on the first try, but if you miss, you can continue to fall through infinitely until you do manage to place a portal correctly. You need to shoot a portal (the same color as your ceiling portal) as you fall so that you can fling over to the other side. Place a portal on the ceiling and the floor. Room 1 has a lot fewer portalable surfaces. In the advanced chamber, most of the puzzles have been made more challenging, requiring alternate methods to solve them

Portal test chamber 15