The last chamber is halted by a large vault door, which holds the frozen humans inside. The final course is very difficult, requiring both players to act as a true team. The players are then dropped into the defunct Aperture testing spheres encountered during single player, and must make use of all elements from the previous chambers along with the Gels that are found in the course. Upon entering, GLaDOS will chime in and explain the significance of Atlas and P-Body's testing and what their true purpose is. This is the final course that unlocks after the completion of Course Four. It will employ elements from the previous courses as well, making it much more difficult as the players progress. During this course, the player will have to make use of both Light Bridges and Excursion Funnels in order to complete these chambers. This course unlocks upon completion of Course Three. In this course, the players must make use of the Light Bridges to both navigate chambers and act as a wall for other chambers as a defense mechanism or a creative way of stopping something from hurtling into acid. This course opens up upon completion of Course Two. This chamber utilizes the effects portals have when an object has both mass and velocity as it enters the portal, meaning the players must utilize both in order to pass this course. Course Two: Mass and VelocityĪfter completing Course One, this course will unlock for players to continue testing.
Pings come in a variety of forms, from a simple "Look" ping, to a "Timer" ping that can be used to coordinate timed events effectively. In this course, the players are given basic tests that emphasize the use of teamwork through portals and pinging, which is a function that allows players to communicate even without text or even through voice. This is one of the first courses available to the player upon entering the Hub, the others remaining locked until the other courses are completed. Checkpoints allow the bot that died to respawn at the checkpoint for shorter travel time to the next testing chamber. As the bots progress, they will cross checkpoints that lead into the next part of the test chamber. The gamemode gives an infinite amount of lives, and GLaDOS will comment on every death that occurs with dry humor or irritability. The destroyed bot will be easily rebuilt seconds later in a chute from the Reassembly Machine. In this campaign, the bots will be notified that their partner has been destroyed and exactly where it did. If either both or one of the bots' stands within range of GLaDOS' monitoring cameras and perform a gesture, it will elicit her response, depending on the gesture performed. She even goes beyond to try and break their partnership by pointing fingers at one or the other. This is the only means of retrieving them back to the Hub.ĭuring the testing, GLaDOS will periodically chime in and say a few choice words, either to bemoan the bots' progress or point out their tiny flaws. Once found and inserted within the device, the players are given a few lines from GLaDOS before she triggers a self-destruct sequence on the duo. In these tests, the bots are then put to the test, so to speak, and must use every bit of knowledge earned about the previous tests in the final one.įor the last chambers of each courses, excluding the fifth, the bots are instructed by GLaDOS to go out and locate a certain disk to be inserted into a DVD player found at the end of the course. Each chamber becomes much harder than the last, with the final test taking place outside the official Aperture testing facilities. There are five official testing courses, each with a number of test chambers within, which will test both the robots' ability to solve the different puzzles as they progress. The portals are capable of maintaining the flow of things, even if it enters a partner's portal, which is essential during some test chambers. Each bot comes equipped with their own Handheld Portal Device with separate portal colors. Players take the form of two robot test subjects built by GLaDOS, Atlas the short and round blue bot, P-body the tall and pea-shaped orange bot that looks like a turret with arms and legs.