While Portal 2 really is a fantastic game, it must be said outright that comparing it to its predecessor is always going to lead to a small tinge of disappointment. Part of this is due to the nature of the modern 5-10 hour game and all of the trappings that come along with that (i.e., "filler" sections and the like), but also part of it is due to something much more ephemeral, and something totally out of Portal 2's (and generally, any sequel's) control – it just doesn't capture that same feeling that I got playing Portal.
Basically, what Portal 2 is, on a gameplay level, is the epitome of the standard sequel – everything is bigger, there's more variety, and what you learned in the first game is put to the test in the second game. This means, aside from a pretty drastically different environment (the idea is that the Aperture Lab from the first game has fallen into disrepair, making everything just a little more grimy than the austere white lab rooms from the original), what you're essentially getting is Portal, but with a few extra toys – namely, tractor beams, light bridges, and two types of goo – speed goo and bounce goo. These tools are put together in fairly ingenious ways by the end of the game – while Portal 2 never becomes extremely challenging, it does force you to consider these puzzle pieces in 3D space, which, if obviously borrowed from the original, is still a pretty mind-bending and fun thing to play around with.
Indeed, that might be Portal 2's greatest strength over its predecessor, which is its exploration of 3D space. Few games have ever been this successful at crafting environments that make sense to traverse in 3D, and the fact that Portal 2 does this using seriously aged architecture in the Source engine is quite remarkable, actually. From an aesthetic standpoint, Portal 2 carves out a very distinctive look with its cute and seriously well-animated robots, juxtaposed against the downtrodden back rooms of the Aperture Science Lab – in the original Portal, we were given just a tiny peek at the inner workings of Aperture, but there are significant stretches of Portal 2 that take place "behind the curtain" and they're pretty interesting, especially when you get to the abandoned labs from decades past.
Unfortunately, these sections also correspond with the most pace-y sections of the game, and while I can appreciate these sections from an aesthetic point of view, from a puzzling perspective, they're a little bit annoying. The actual testing lab levels are great fun because they're specifically designed as puzzles, but the gigantic back room puzzles are too dark and often have too uninteresting of puzzles to hold much interest. I found myself just simply trying to find a white wall for too long, rather than constantly puzzling and tinkering, to really enjoy these sections. Now, Valve are quite clearly master storytellers, and these sections are quite funny (as is the rest of the game, of course), but from a gameplay perspective, I kind of dreaded going into the backrooms a lot of the time simply because they weren't as much fun to play as the testing labs.
I've alluded to the story, and once again, Portal 2 doesn't quite capture Portal's perfection, if only because Portal was such a novel experience and so tightly written. With that being said, the additions Valve have made to the story have been mostly fantastic – Stephen Merchant as your pal Wheatley steals the show, and I'd be surprised if he doesn't show up in more voice acting roles because of it – he was brilliant on Extras, but this might be his best role yet. And J.K. Simmons is, well, J.K. Simmons, and he's always goddamn hilarious.
Initially, GLaDOS seems a bit underwhelming. Whereas in the first game, her transition from calm, gentle (if sardonic) guide to murderous AI gone rogue was surprising, here, when she has "all phasers set to kill" so to speak right from the beginning, it's almost expected, and Portal has made a name for itself as a game series that constantly surprises. But towards the end of the game, when you and GLaDOS have, um, "teamed up" (not to spoil anything, of course), she actually becomes a surprisingly human and deep character. It's a subtle shift, but it's totally amazing. And of course, she's still voiced with that same deadpan wit that made Portal so enjoyable.
What Portal 2 does, effectively, is not so much make any wider statements about the world (though the idea that "absolute power corrupts absolutely" is on full display here), but offer a funny and subversive look at the mythos of its own world, and this is ultimately what makes Portal 2 so successful. The way in which the gameplay (almost never broken up with cutscenes, thank god) and this story of escape and redemption are intertwined is seriously about a lightyear ahead of most other developers. Valve truly understands how to write for the videogame medium, and whereas most videogames are straight up incomprehensible with their plots, Portal 2 will likely stand shoulder to shoulder with the best written pieces of this year in any medium. I once bemoaned the absence of the videogame comedy, but Portal 2 is definitely the standard-bearer in that regard. And what's refreshing is that Valve isn't trying to make any sort of pretentious statement with this game – they're just taking you on a fun ride and doing it with verbal wit and amazing style.
So the game is too long and with too much downtime; the story isn't as shocking or perfect as Portal's; and the gameplay is only minorly altered. But there are millions of games worse than Portal, and that doesn't make them bad games. Indeed, Portal 2 is likely going to be one of the best games of the year, and Valve pretty much did everything they could within the confines of a traditional sequel here. Once I stopped consciously comparing the two games, I found Portal 2 to be one of the most enjoyable videogaming experiences of this year, a really fun ride while it lasted.