Portal 2 is a computer game. It is the sequel to the game Portal, but you don't need to have played the first game to appreciate the second one. Portal and Portal 2 do not involve running around shooting aliens, nor do they feature magical encounters. Instead there are a series of logical puzzles in which you must escape from a chamber by crossing pits, operating switches, disabling dangerous laser beams and so on. Probably the game it is closest to is the classic Lemmings from the 1990s. The original Portal game was quite short, but Portal 2 is a full computer game that will keep you busy for days or weeks. Portal 2 was released in 2011 and is available on Xbox 360, Playstation 3, Windows and Macintosh. It is produced by Valve Corporation¹.

Portal 2 is fun. It is a non-violent game which does not require a huge amount of physical dexterity to play. There are a few of the puzzles that require some careful timing, but most can be thought about, planned and then carefully set up, so if you are not the fastest on the keyboard, you can still get a lot from this game.

Portal 2 is funny. Not only is the commentary provided by the on-screen characters amusing, but there are many hilarious touches, such as the cute 'turret' robots, the muttering blocks made from discarded robots and the space-obsessed robot at the end of the game.

The Main Characters

• Chell - you are playing the part of the character Chell, who is trapped in the industrial complex of Aperture Laboratories and is trying to escape. Although you don't normally see yourself, you occasionally catch glimpses of yourself in the distance. You are a young woman with medium-coloured skin and dark hair tied back in a ponytail. You are wearing a white T-shirt and orange trousers. You do not speak at any point during the game.

• GLaDOS - a computer with a female voice, GLaDOS initially controls the whole of Aperture Laboratories. In a former story (the game Portal), you defeated and disabled GLaDOS (she describes it as 'murdered') so she is out to get her revenge on you. This involves trapping you in a series of puzzles ('tests'). You must use your ingenuity to escape from the test chamber, but there is always another, more difficult test to be completed. GLaDOS reckons she has enough tests lined up to keep you going for the rest of your life, and as you progress she taunts you, promising you freedom at the end of the next test, then admitting that she lied. In the game, GLaDOS is voiced by American voice actor and soprano, Ellen McLain.

• Wheatley - a small, stupid robot about the size and shape of a football, with an eye-like camera lens on one side. Wheatley is initially disturbed at your treatment and tries to help you escape. He is totally unsure of himself, and constantly changes his mind, stumbles in his speech or repeats himself. Wheatley is voiced by British comedian Stephen Merchant.

• Cave Johnson - voiced by American actor JK Simmons, the character of Cave Johnson is never actually encountered in the game, but recordings of his voice are played at various times. He was the CEO of Aperture Laboratories. His gung-ho attitude in the 1950s recordings gradually turns more bitter as his company gets into difficulties and he himself starts to suffer from the ill-effects of the careless testing of dangerous substances in his lab. You don't have to pay attention to Cave Johnson at all - you can finish the game without listening to a word he says - but it provides a convincing and amusing background story, explaining the existence and original purpose of the whole Aperture Laboratories complex.

What You'll Meet Along the Way

• Test Chambers. These are giant rooms. Each test chamber has a door by which you came in, which shuts and cannot then be opened, and a separate exit. The exits are always clearly marked. It is rarely easy to get to the exit - there are often apparently insurmountable obstacles in the way. Even when you get there, the door may be locked, and the only way to unlock it is by operating a switch in some other part of the room. The presence of the entrance and exit doors divides the game up into different 'levels', but in some parts of the game the chambers have no clear boundaries as the whole complex is falling apart and walls may be missing.

• A portal is a gateway or 'wormhole' that joins two places together. Stepping into one end of the portal, you immediately come out of the other end. The two ends of the portal appear as a blue and an orange ellipse. These can be fired onto any suitable surface by the portal gun which you acquire early in the game and keep with you throughout. (Surfaces must be smooth, flat and painted white.)

  In the early stages of the game, the use of the portal is quite simple. You fire a blue portal end onto a nearby wall, fire an orange portal end onto a distant wall and step through the portal, avoiding all the pits and hazards in between.

  You can do much more, though. Objects can fall or be thrown through a portal. Momentum is preserved, so that if you are moving fast as you enter, you emerge moving fast as well. If both portal ends are in vertical walls the effect is obvious, but more unusual effects are produced when one end of the portal is on a horizontal surface. Falling into a portal end on the floor, you can emerge from the other end which you have positioned on a wall, and your vertical speed is converted to horizontal speed, which can be useful for jumping across a pit. Positioning a portal in the floor and with the other end directly above it in the ceiling, you can fall downwards indefinitely, accelerating to great speeds. Laser beams, light bridges and transport tubes can also travel through portals.

• Pits, which may be full of water or bottomless, make it difficult to reach some parts of the chamber. In the early stages of the game there are very few ways to kill your character - falling into water is one of the few. (As the game progresses you will encounter more and more). If your character does die, you just start the level again.

• Switches control some features such as the exit door, and certain ramps and lifts. Switches are large and obvious. They are clearly marked, with a dotted line linking them to the item they control, so it's usually obvious what they do. You can operate a switch by standing on it, but normally its effect is undone as soon as you step off the switch, so you need to find something you can leave permanently sitting on the switch. There are blocks known as weighted storage cubes in some places which can be picked up and placed on a switch.

• Powerful lasers shine out of the walls in some places. Don't stand in the way of a laser as it will burn you and you will die. You can divert the path of a laser by sending it through a portal, and there are special lens blocks which can also divert them. Lasers have a few uses, one being that there are special laser-operated switches.

• Turrets are cute little robots. They talk to you in pathetically cute voices, but if you get into their line of sight, they attack with machine guns and you die. Turrets are stupid, though; you can creep up behind them and knock them over, rendering them powerless.

• Light bridges are long sheets of light you can walk across.

• Launchers are spring-loaded devices which hurl you through the air.

• Blue Gel can be spattered over surfaces to make them bouncy.

• Red Gel appears in the later levels - applying red gel to a surface makes you accelerate as you move across it.

• White Gel is the rarest type of gel. Although there are many smooth, flat surfaces in the game which might be useful for placing a portal, you can't use them as they are not painted white. White gel turns out to be the white paint that allows a surface to accept a portal.

• Transport Tubes are tubes of light that support you in the air and move you along. They're very useful for crossing large pits, but you can't control the speed or direction you move.

The Story

The action of the game has a natural story behind it which is revealed by what you see around you, by comments from GLaDOS and Wheatley, and by recordings of the voice of Cave Johnson, a character from the past who created Aperture Laboratories. We won't give too much away here, as part of the fun is finding out what is going on. There are three main sections to the game:

• Escaping from GLaDOS

  In the first section, you are forced to solve a series of increasingly difficult tests, but Wheatley appears and opens a separate route into the hidden corridors of the complex. You and he devise a plan to defeat GLaDOS, replacing her evil personality in the central computer with Wheatley's benign one.

• Finding your way back to the Control Room

  Wheatley is driven mad by power. He throws you and GLaDOS (now housed in a tiny computer powered by a potato battery) into a rubbish chute. You must use your ingenuity and the portal gun to work your way through the mainly deserted and dilapidated industrial complex, which is much bigger than you originally thought. GLaDOS devises a plan to defeat Wheatley by exposing him to a logical paradox, but he is too stupid to be affected by it.

• Escaping from Wheatley

  Now in control of the system, Wheatley gets pleasure from watching you solving more 'tests'. The first of these is trivial but they rapidly become very difficult puzzles. Then he decides he has had enough and tries to kill you. At this point, you must avoid potential death traps and make your way to a final showdown with Wheatley in the control room.

Two-Player Game

Portal 2 also includes a two-player version, where you and a friend control two robots: a tall, thin one and a short, round one known as P-body and Atlas and reminiscent of Laurel and Hardy or Sullivan and Mike Wazowski. Each robot is equipped with a portal gun. There are plenty of opportunities to see the two robots being crushed or destroyed by lasers as you fail to line everything up just right for the solution of the problem.

The two players can be both on the same computer/console device, or can be in different locations connected via the Internet². The screen is split in two with the left side showing the view of one player and the right the view of the other player. Most puzzles require the co-operation of the two players - for example, one player may have to fire the other across a barrier, then the second player open a portal for the first player to step through. Some doors can only be opened by two switches being pressed simultaneously. And the switches may be on the ceiling! You get the idea.

If the two players are sitting side by side, there's no great difficulty in co-ordinating these moves, but if the other player is remote, there are a number of controls which allow your robot to make gestures to the other player, to mark a spot on the screen where you want the other player's robot to stand or to countdown - 3, 2, 1, Go. This last one is important in puzzles where two switches have to be operated simultaneously.

With two portal guns, it is possible to open up two portals simultaneously. One gun fires yellow and red portal ends while the other fires light and dark blue ones. The technique of positioning a portal end directly over the other end of the same portal and accelerating through an endless fall, while requiring great dexterity in the single-player game, is pretty easy to manage in the two-player version. One player can fall endlessly while the other player can fire the portal end to release them from the loop and hurtle them across the chamber.

The two-player game appears to be much simpler than the single-player game. There is a very simple back story, and there are only about 30 levels. You still get to hear GLaDOS's voice insulting both robots at every available opportunity.

Because the two-player game is very much just puzzle-solving, it is important that you play it with someone who has not played it before - otherwise, they will end up solving all the puzzles and you'll just tag along, and won't get very much from the experience.

Conclusion

All in all, Portal 2 is one of the most enjoyable games of recent times. It suits a player who doesn't want to shoot anybody, likes using their brain and enjoys a good laugh.