All the way back in 2007, Valve Corporation decided to reward console gamers with possibly the best value in the history of gaming with The Orange Box. Prior to this point, Valve's wildly popular hit Half-Life 2 had been available exclusively to PC gamers. Valve more than rectified this with The Orange Box, combining five great titles into one retail package. While each game was great in its own right, one game stole the show. That game was Portal.

Portal was a completely original first-person puzzle game in which players found themselves attempting to navigate a series of test chambers using only a gun which can create two portals, allowing the player to pass through one and appear out of the other. This seemingly simple concept was incredibly addictive and led to surprisingly complex physics puzzles in which players had to take full advantage of the laws of gravity as well as their environment.

This game was well served by its inclusion of Wheatley, who is voiced by Stephen Merchant—he collaborates with Ricky Gervais and works on The Office and Extras—the artificial intelligence responsible for creating and managing the series of test chambers you must complete. This character is possibly one of the most entertaining and hilarious I've ever encountered in a game, and her presence, along with the fantastic puzzles, made Portal an instant hit.

When Valve announced that they would be making a sequel to this innovative title, I was both excited and a little concerned. The original Portal could easily be completed in a couple of hours, and it wasn't clear to me that its unique brand of narrative and gameplay could be sustained throughout a full-release game with a playtime of 15 to 20 hours. Fortunately, my concerns were misplaced as Portal 2 turned out to be the smash hit of this summer.

Once again, players find themselves in the role of silent protagonist Chell as she attempts to escape her imprisonment at Aperture Laboratories using her familiar portal gun while navigating a whole new set of test chambers. This game is not just more of the same, however, as players are introduced to two new characters. The first, Wheatley, is another machine with aspirations of overthrowing GLaDOS. Cave Johnson, the second, is the late founder and CEO of Aperture Science, who is voiced by J.K. Simmons, famous for numerous roles including Juno's father in Juno and J. Jonah Jameson in the Spiderman trilogy. Both of these new additions possess all the character and humor of GLaDOS and make Portal 2's story an unforgettable experience.

Portal 2 isn't just about new characters and story, however, as gamers are presented with a whole new arsenal of environmental tools. This includes a series of three gels which can be moved around the test chamber with cleverly placed portals and then used to enhance one's leaping and running abilities or to create new surfaces on which to place portals. All of these new mechanics fit in perfectly and greatly enhance Portal 2's ability to remain entertaining over the course of its significantly greater length.

In the end, Portal 2 captures the essence of everything that its predecessor did right and recreates that magic while simultaneously expanding it to fit the confines of a standalone retail release. Those who loved Portal will fall in love all over again with Portal 2, and those who didn't care for the original won't find much to change their minds. This is both Portal 2's gift and its only downfall; it was a masterpiece of the puzzle genre, and Portal 2 perfects every aspect of that game, but for precisely this reason it lacks the originality and novelty of its precursor. Despite the fact that this game didn't leave quite the magnitude of impression as the first, it is still my top candidate for game of the year to this point, and I give it a 9.5/10.