By now you've all heard the acclaim heaped (deservingly) upon this little gem of a game created a group of Digi Pen students who were hired on by Valve. I've just begun learning the process of level creation to make my own Portal levels, and it got me thinking back to some of the praise given to the game. There is one notion that I'd like to comment on, and that is the perception that key to Portal's success is the game's shortness. Well, yes and no.

What concerns me is that people seem to think that the shortness alone is the reason the game doesn't overstay its welcome. But I think a fine distinction needs to be made here: Portal isn't great because it's short, Portal is great because it is exactly the right length. Just when the early levels seem to indicate that the game will be too simple, they get harder. Just as you think the game is about to unfortunately end, it opens up to reveal additional play. And just as you begin to wonder if that additional play is going to go on too long, you are presented the game's wonderful climax.

Intrinsic to the game's appropriate length are its narrative touches. I originally feared that the AI "narrator" GLaDOS would run out of clever lines, but she never does, and though humorous her dialogue often offers trickles of backstory that keep you interested in pressing on. Also, the occasional hideouts of other test subjects you stumble across do wonders for making the game feel bigger than it initially appears, and also relieves some of the potential loneliness a player might experience in the stark test chambers (GLaDOS and the gun turrets contribute to this as well, oddly enough considering they are a menace).

Many other games, even the good ones, fail to match this balance that makes the player feel like his experience is complete without feeling drawn out or artificially extended. It's a tricky thing, because tied into the narrative (to whatever extent the game poses one) keeping the game interesting, you've also got to estimate how long the gameplay interactions will remain engaging. Portal does a good job of making you beg for more, but delivering it at a very deliberate pace. You start with no portal gun, then you have a gun that can only shoot one portal, then you finally earn two-portal capability, and then the rest of the levels layer in challenges like buttons, turrets, moving platforms, and such to challenge your understanding of the gun's operation.

Game developers should focus on creating a serious of experiences that allow the player to learn their gameplay systems, and experiment with them as well. Once this is accomplished for the current stage in the game’s progression, move on! Add additional gameplay systems to challenge and excite the player. Remember to support your mechanics by developing your narrative. Eventually you will sense that enough gameplay and story have been delivered to satisfy players (while leaving them wanted just a little more). And then comes the next important step: end the game!

-Jason

P.S. I made a video of some fun I had with the turrets and cameras in Portal, if you want to check it out click here.