The Cake is a Lie.
Valve really do not do much to innovate any genre of games they make, at least in the gameplay aspect. Sure, they may have created the most innovative gaming service when they released Steam, and created a great way of story-telling in first person, but how the games they create play haven't really been something they've been too inventive with. Well, now, that Portal has been released, you can no longer say that.
Portal is genius. Pure genius. If you jump into the game not knowing or have seen the game at all (though that would be very difficult to do) you will be scratching your head at the start, wondering what the hell is going on.
The story in Portal is told in a rather odd fashion. Glados, a "computer lady" will talk to you throughout your mission. That mission being you, Chell, going through a series of these Testchambers. Testchambers that will require a whole lot of intelligence and experiementing with to pull off. Why you are going through these Testchambers isn't really stated, as far as I know, but when you wake up in the training facility you are guaranteed cake when you finish your training.
First and foremost, you need to understand the main gameplay mechanic. You have a gun. A portal gun, which is technically dubbed Aperture Science Portable Device. This portal gun can shoot two different colored portals, yellow and blue. At the start of the game you won't even have the gun. All the portals will be placed for you. A little bit farther into the game you get the gun, and you have the ability to shoot only blue portals. Then, you eventually get to shoot both of the portals, blue and orange. At this point, the game gets ridiculous.
The special thing about these portals is that they link eachother together. Meaning, if you shoot a orange portal and a blue portal, and walk through the blue one, you'll come out where you placed your orange portal. This turns a place that appears inacessible at first, and would be inacessible in any other Source game, an easy capability of reaching. This mechanic does work well, usually. When walking from a portal on a wall to another portal lying on the wall the transition seems seemless. But, when you are flip flopping between two portals, both places on the ground, your gonna tip and turn upside down, it's really gonna be complicated, and even hours into playing the game you still won't exactly understand how everything works.
It gets much more co mplex than that, however. Using momentum, physics, and speed will give you a great advantage in completing the latter Testchambers in the game. Jumping into a portal from a high location will send you flying out the other portal at a very high speed. And, when you're bored, you can always place to portals parralell to eachother and just have another never ending chain of you just going in and out of the two portals.
In the end, this puzzle game is a simple, "Get-to-the-goal" type of game. Along the way, you'll have to place companion cubes on red buttons, flip switches, get electric balls into their destination to activate moving platforms or open doors blocking you from reaching your end point. Dotted lines on the floors and walls will indicate to you what you will have to do to open or activate what.
The pacing in Portal can be a little bit weird near the end, though that may just be caused by the increasingly difficult level design as the game continues into the game's later levels, but it's the kinda game that will only take you 3-4 hours to complete. The last level of the game is also 3-4 times longer than any other level in the whole game.
As I said, the game can easily be completed in a mere 3-4 hours, but you can always take on the advanced challenges and the timed challenges. Also, like all Valve games, there's huge community support for this game, so you can download all the map packs you want and have never ending hair pulling, that is if you play on the PC version. Unfortunately, no custom maps for the console versions. (Hint: Get it on PC!) The $20 price tag for Portal is definitely a little steep for the short, but great experience it offers. Though, if you purchase The Orange Box, you'll get it and 4 other great games for a cheap price. But, if, for whatever reason you plan to buy this game stand alone, you may find it a little bit expensive for what you're getting.
Portal is a great, brand new, fresh idea that can be worked on and tweaked to make even more crazy puzzles that will have you raising an eyebrow. I look forward to future ideas of Portal being made into something even better, such as putting four different colors into the game, eh? In the meantime, you can go download some of the user-created maps for Portal, even if some of them, and by some of them I mean most of them, are really actually physically impossible to complete.