Portal Test Chamber 13 (Bonus)

This is the first Bonus map of the game. It is unlocked when the original Test Chamber 13 has been completed.

Hazards

 * High Energy Pellets
 * Cube Hazard

Strategy
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Portals

 * When retrieving the Weighted Storage Cube, try to use the same portal that you placed on the bottom.
 * Place a portal on the wall next to the Heavy Duty Super-Colliding Super Button in the next room.
 * Make a save before attempting to throw the Cube onto the other button.
 * Walk though the same portal on the wall near the button when reaching the exit.

Steps

 * Use floor-to-floor portals to reach the Cube and Button.
 * Fire the same color portal that you exit out of. This will not make the step counter go up.
 * Make two portals to make to land on the button.
 * Be sure to get within range of the cube to pick it up before making a portal to the top button in the next room.
 * Portal the cube onto the other button. If you can't see it, revert to an earlier save.
 * Place a portal on the floor, and another on the floor near the exit.
 * Use floor-to-floor to get as close as possible to the Chamber lock.

Time
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 * Grab the Cube though the portal, don't waste time traveling into the portal to place it on the button.