Note: This article contains minor spoilers about the gameplay and storyline. If you want Portal to be a complete surprise, we recommend that you only read the pros and cons and … play the game.

        The first time I encountered the notion of portals was when 3D Realms announced Prey in 1997 and the impressive demonstration at that year’s E3, although the competition was running high, with information leaking about the future of FPS games – trailers from Half-Life or Unreal. After being in the shadows for a while, Prey was finally launched, but the usage of portals was restricted, even blamed by some of the developers of the game for leading to the delay of the project because of the complexity in programming for collision detection, rendering and even sound design because of multiple possible sources.
        For Portal it all started with a game designed by a few students (Narbacular Drop), based on a concept according to which the player can create their own portals within levels. This presentation became a long-term collaboration with Valve, which started more like a technological demo, but ended up being one of the most awaited titles of the year. Integrated into the Orange Box, Portal was seen as more of a curiosity, a simple annex to what everyone was really waiting for, Half-Life 2: Episode Two and Team Fortress 2. The surprise was huge, as the game generated a great deal of interest after launch and received critical acclaim from both players and press.
        The main part of the game, as the name indicates, is the portal concept – “doors” that are apparently a curiosity of the laws of physics. They can be created on walls, ceilings or floors and can transfer an object or player to a destination-portal than exists in another part of the level (the transfer is a two-way road). Even if the game uses a first person perspective, it’s not a real FPS because you don’t have any weapons, you have to make due with a portal gun that can initially create one portal and then gets an upgrade and can be used for both exit and entry.

        It all starts with the lead character (a female no less), who wakes up in an isolated room, gets up from a bed that seems transcended from a futuristic hospital and get the first information from a computerized voice tat explains the basic use of portals. And so the adventure begins, 19 levels of testing. The only task the main character has to accomplish is to get from the lift that takes her to a level to the next one, at the end of that room. Of course, as the game progresses, these puzzles become more and more difficult and new concepts that can be used to solve them are presented.
        Portal takes the form of an experiment and you soon find out that at the end of the 19 levels there is a delicious reward – a cake! Although there are small problems in getting across rooms, as you progress things get more complicated and along with portals there are energy balls we saw in Half-Life 2: Episode One, that cannot be captured for transportation, but can be directed using portals towards special locations that use their energy. We also deal with large buttons which open doors, once a weight is placed on them – this is where the companion cube comes into play, which that can be moved around using the portal gun.