Chapter 4 - Part 4: Chamber 21

Chapter 4 - Part 4: Chamber 21

sp_a2_bts1.bsp Jail Break

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Chapter 4 - Part 5: Escaping the Test

sp_a2_bts2.bsp Escape

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This is the thirtieth level of the game, and the final part of Chapter 4. This level is set within a Test Chamber and the maintenance areas of the Aperture Science facility. This level advances the central plot, and does not contain any significant Portal-related challenges.

Hazards

• Goo
• Turrets
• Neurotoxin

Walkthrough

Intended Chamber Solution

• Place a portal on the wall where the Hard Light Bridge ends and the other one on the left side of the exit.
• Go through the portal and push the Switch.
• Continue to walk to the cube.
• Put the cube on the button.
• Use the portal again to proceed to the chamber lock.

Actual Course of Action

• Wait for Wheatley to open the wall and run to the Maintenance area.
• Run to the left and continue forwards.
• Turn right on just before the catwalk ends.
• Turn left and jump down. Continue by to the right up the stairs.
• Run forward as much as you can. Turn left and continue running.
• Jump down on the left side.
• Use the Bridge and run away from the Chamber until the Bridge disappears.
• Turn to the opposite direction and continue running.
• Jump from the catwalk to the area between chambers and run forward until you get to the wall.
• Pick up the turret and knock over the turret behind it.
• Turn left and go behind the tube and knock over the third turret.
• Let go off the turret (make sure it gets knocked over).
• Open a portal on the wall near the third turret. Shoot the other portal behind the panels where the third turret is. Go through the portal.
• Run to the right and follow Wheatley until a turret is revealed on the left.
• Get rid of the turret by using a portal and continue following Wheatley. Enter the elevator at the end of the catwalk.
• Wait for the elevator to stop and go through the door.

Video walkthrough

Download demo files: Part 1 – Part 2

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Related achievements

SaBOTour Make a break for it

Good Listener Take GLaDOS' escape advice

Trivia

• If you take too long to escape the test chamber, GLaDOS will fill the room with neurotoxin.
• If you fall for GLaDOS's attempt to trick you back into testing, she traps you and fills the room with neurotoxin.

Music

An Accent Beyond by Aperture Science Psychoacoustics Laboratory [2:58] | Download | Play

Gallery

Behind the scenes Concept.   Wheatley interrupting the Test Chamber.   The escape begins.   GLaDOS attempts to tempt the player back to testing.

Challenge Mode

Jail Break

• Map name: sp_a2_bts1.bsp
• World record: 39.70 by unity
• Portals: 2
• CM (Challenge Mode) Available: Yes

Escape

• Map name: sp_a2_bts2.bsp
• World record: 25.96 by Mel
• Portals: 0
• CM (Challenge Mode) Available: Yes