Portal Test Chamber 15 (Advanced)
This is the third advanced chamber of the game. This version is unlocked when the original Test Chamber 15 has been completed. It has the extra challenge of making the flings harder, one more Material Emancipation Grill in the first pellet puzzle, different ricocheting for the second pellet puzzle, faster moving Unstationary Scaffolding, and trickier button presses.
- Pellet hazard.
- As you enter this chamber, place a portal up in the tile ceiling and place a portal down on the white tiles.
- You will need to do a terminal velocity. Quickly place a portal in the white wall panel.
- Enter the second part of the chamber. The portals are prevented by the fizzlers. If you walk through the fizzler, the portals will close.
- Place a blue portal where the Pellet launchs straight and the other portal where the Pellet can go through fizzler.
- After the pellet goes through the portal, quickly go through the fizzler and fire the portals that Pellet goes to the receptacle.
- As soon as the Pellet enter the portal, quickly go through fizzler again and place portals that Pellet enters the receptacle.
- Enter the Victory Lift, then go to the end of the hallway that leads to the third part of the chamber.
- Since there is no stairs, you'll have to place a portal up and the portal on the white tiles.
- Enter the portal and place the portal in the pit and jump through the portal and quickly go through the Emancipation Grill. You should now on the other side of this chamber.
- Shoot a portal on the wall panel and place a portal on the floor. You should now land on the other side of glass.
- As soon as the pellet goes theough the portal, fire a portal that lead a direction to bounce. Fire a portal quickly that the Pellet bounces around the room and goes into the receptacle.
- Repeat the same process as the momentum. It will take you back to the place where the exit located.
- In this test, platforms are moving faster than usual, so you'll have to quickly step on the moving platform and place a portal on the other wall before it continues moving.
- At the end of the moving platform corridor. quickly place a portal to the last part of this chamber.
- Enter the first lift to the first switch. Place a portal up to the ceiling and enter the second lift.
- As soon as the lift goes down, place a portal near the lift.
- Press the switch and hurry to the another switch and press it, then quickly place a portal that Pellet leads to the receptacle.
- After the Pellet goes in the recptacle, enter the Victory Lift and into the Chamberlock.
Beat two Portal advanced maps.
Beat four Portal advanced maps.
| Vanilla Crazy Cake|
Beat all six Portal advanced maps.
- Portal Test Chamber 13 (Advanced)
- Portal Test Chamber 14 (Advanced)
- Portal Test Chamber 16 (Advanced)
- Portal Test Chamber 17 (Advanced)
- Portal Test Chamber 18 (Advanced)
- Portal Test Chamber 15