A physics-based puzzle game that prides mental acuity over murderous mayhem, Portal 2 is the phenomenal follow-up that Valve's 2007 hit deserved. Unlike that predecessor, a too-brief supplement to the Half-Life 2-centric Orange Box bundle, this sequel is a proper title unto itself, which merely means more of the brilliance that defined the original.
Once again assuming a typical first-person POV as heroine Chell, you awaken after an accidentally long hyper-sleep to find that Aperture Labs, the underground research bunker you call home, has fallen into cataclysmic disrepair. While led out of the crumbling subterranean compound by robot "personality sphere" Wheatley, your sentient computer-system nemesis GLaDOS is accidentally awakened, and remains eager to put you through more tests as she slowly rebuilds the facility. This means conquering a series of rooms in which finding a way to the exit involves utilizing your trusty portal gun, a device that can be fired at certain surfaces to generate connecting time-space gateways. This wormhole gimmick is a seemingly simple construct—you fire a blue portal with the right trigger and an orange portal with the left trigger, and pass through one and out the other—that Valve milks for every last drop of brain-teasing creativity, especially as one progresses through the game's prolonged nine chapters, which soon require far more than simple A-to-B travel.
Everything that was excellent about the prior saga returns, including movable blocks, remote turrets, and the disorienting experience of free-floating ad infinitum through dueling portals. Far from content to rest on their laurels, however, the Half-Life 2 producers' newest masterpiece ups the ante in innumerable ways, from springboards that send one flying over moats and into tractor-beams, to three different types of gels—causing surfaces to become bouncy, super-fast, or compatible with your wormhole weapon—that complicate navigation of each stage. Newbies will likely appreciate the gradual escalation of difficulty, with each new environmental twist introduced in a relatively easy level, and then expanded upon in subsequent, taxing trials. But one of the game's joys is its difficulty, its demand for serious intellectual engagement with its intricate puzzles, which are all the more clever for the ways in which they simultaneously utilize, and yet subtly play off of, traditional FPS mechanics.
The game's look and feel will be wholly familiar to anyone who's experienced a Halo or Call of Duty. Nonetheless, in its co-option of a perspective (and its attendant controls) typically associated with homicidal adventures for a fundamentally cerebral, bloodless affair, Valve's latest turns out to be a beautifully rendered and addictively engaging piece of form/content subversiveness.
As a single-player quest, Portal 2 is so consistently inventive that it can be downright exhausting, though alleviating the strain of its toughest segments is the game's laugh-out-loud humor, which comes in the form of tutorial graphics and PSA displays that playfully mock dystopian sci-fi conceits, as well as its cast of characters: Wheatley (voiced by Stephen Merchant), your wisecracking, self-deprecating British sidekick; Cave Johnson (J.K. Simmons), the increasingly deranged head of Aperture Science; and iconic baddie GLaDOS (Ellen McLain), whose politely sarcastic insults to Chell (often about her nonexistent weight issues) are caustically hilarious. Visually, the proceedings remain industrial-design spartan, but they do eventually open up to reveal greater scope and scale, especially during trips through locales GLaDOS would prefer you not venture.
Moreover, as superb as its solo mode is, even more impediments await via a unique cooperative campaign whose two-player traps are just as devilishly complex, and also further rework tried-and-true FPS aesthetic and interface formulas into something thrillingly unique. As innovative, challenging, amusing, and downright entertaining as they come, Portal 2 refutes the dim-witted contemporary adage by proving that the most fun comes from turning one's brain on.