Portal
Portal is a puzzle adventure game by Valve that introduces a unique new mechanic of shooting portals to teleport yourself or objects from one place to another. The game is fairly short but does have some interesting level designs. This walkthrough will give you a video and written solution to each of the 20 puzzles.
You begin by waking up in a small lab room. Your only companion is the sound of a computer called GLaDOS. She takes you through a series of puzzles to test your skills but it turns out she has more sinister plans for you.
Portal Walkthrough
Portal is a puzzle adventure game by Valve set in the Aperture Science Laboratories. You must complete a series of puzzles by opening portals and manipulating the environment to find a way to the exit. Along the way the computer, GLaDOS becomes more and more hostile. Eventually you’ll need to escape the puzzles and confront GLaDOS.
Portal was released on the 10th of October 2007 and received overwhelmingly positive reviews. In 2008 it won the Game of the Year award as well as Best Game Design. In 2011 Portal 2 was released and features the return of GLaDOS and multiplayer levels with their own storyline.