Valve's Portal 2 is the sequel to the first person puzzle game 'Portal' which was originally included in 'The Orange Box' in 2007 as an extra. The game is a lot like the first one but with more features to make more interesting and challenging puzzles and with a brand new co-op mode!

You start the game playing as Chell, the same test subject you played as in the original game. You should see you are in what looks like a hotel room with an announcer talking to you. It turns out you are in Aperture Labs, the testing laboratories you had to escape from in the first game. You eventually get out of this room with the help of a robot called Wheatley, voiced by Stephen Merchant. Testing will then begin!

The first few tests are very simple and it just requires button pushes and simple puzzling to get portals to appear. You have to use these portals throughout the game to solve each puzzle either by using them to simply walk to an unreachable area, or by using momentum to fling yourself to unreachable areas. As the game goes on, you acquire an Aperture Science Handheld Portal Device to create blue and orange portals and the puzzles start to get a lot more difficult and new features to take into account come in. Portal 2 has a bit more of a story to it as the first one. You get to learn about the old Aperture Labs and like the first game, there are many hidden areas which add to the story. The whole single player story spans over nine chapters which comes to around 7-9 hours depending on how quickly you can solve the puzzles

Finished the story? No problem! Grab a buddy and you can play the all new co-op mode! In this mode, you control robots Atlas and P-Body to solve puzzles designed especially for this co-op mode. Throughout the tests you will have to use teamwork to help each other solve puzzles which have similar features to the puzzles from single player. There are also many moments where you have to rely on your 'Partner in Science' to get you across a dangerous area... or they can just move their portals and drop you to your death! Throughout the co-op mode you will get GLaDOS, the main antagonist from the original game talking to you, trying to turn you and your co-op partner against each other. You also gain some 'Gestures' as you progress through co-op which allow you to perform simple, fun actions such as waving, dancing, hugging and giving your partner a high five.

'Portal 2' is another fantastic game from Valve and I highly recommend it. I genuinely cannot think of any bad points about it because I loved the humour, action and how clever some of the puzzles are so much. If you own a PS3, you can buy it new and get a free download for the PC version as well as a Steam overlay on your PS3 version of the game to allow you to play Portal 2 with your friends who own the PC version!