As the tests progress she eventually acquires the first "portion" of the Aperture Science Handheld Portal Device, allowing her to place blue portals but not orange ones. See more

More buttons and boxes.At the end of the chamber, GLaDOS states that the next test chamber will not be monitored, as "part of a required test protocol." See more

This chamber contains two boxes and two buttons. GLaDOS reveals that "our previous statement suggesting that we would not monitor this chamber was an outright fabrication." This begins to hint at her malicio… See more

In this chamber, the Aperture Science High Energy Pelletis introduced. Also introduced are brown walls that do not allow portals to be created on them. These are seen commonly throughout the rest of the game. See more

A so-called "impossible" test chamber utilizing buttons and cubes. The chamber does not mark the introduction of Emancipation Grills but rather the introduction of Emancipation Grills as a part of the puzzl… See more