Gameplay revolves around the Aperture Science Handheld Device (also known as the “Portal Gun”, or ASHPD, the acronym), a device that can create an inter-spatial portal between flat planes, allowing instant travel and a visual and physical connection between any two different locations in 3D space. In Portal, the player controls Chell (as she is named in the game credits), a test subject in the Enrichment Center. In another chamber, GLaDOS boasts about the Weighted Companion Cube, a waist-high crate with a single large pink heart on each face. GLaDOS also directs Chell through a live-fire course she claims is designed for military androids as a result of “mandatory scheduled maintenance” in the regular test chamber (though as noted before, GLaDOS may not necessarily be truthful in anything she says). The test chambers become increasingly dangerous and difficult throughout the game as Chell proceeds. GLaDOS’ actions and speech suggest insincerity and callous disregard for the safety and well-being of the test subjects. Chell proceeds into the Enrichment Center, interacting only with GLaDOS over the course of the game. Chell is promised cake and grief counseling as her reward if she completes all the test chambers. This part of the game involves distinct test chambers that the player has to complete to go on to the next test chamber. The game begins with protagonist Chell waking up from a stasis bed and getting instructions and warnings from GLaDOS about the upcoming test chamber experience. The plot of Portal is revealed to the player via audio messages from GLaDOS and side rooms found in the later levels. The “portal gun” and the unusual physics it creates are the emphasis of this game. The goal of each chamber is to reach an exit point, represented by a circular elevator. he game consists of a series of puzzles which must be solved by teleporting the player’s character and other simple objects using the Aperture Science Handheld Portal Device. Portal is a single-player, first-person shooter puzzle game developed and published by Valve Corporation.

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