In preparation for the release of Portal 2 on April 19, Valve has released a comic (which can be found here) detailing the events between the two games, as well as some of what happened before Portal. This comic, called Lab Rat, follows a crazy employee who is likely responsible for all of the drawings and writing found during Portal, as well as giving some much needed background on Aperture Science and Chell. While it was neither as profound nor as long as The Sacrifice comic, it is still a really good read, I highly suggest it.

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