Bargain boxes. For years, they were the domain of shovelware and repackages of ancient titles, and not much else. Generally speaking, if you saw a bunch of games being sold together in one box, you could rest easy in the knowledge that the package, as a whole, was either terrible or ancient. With The Orange Box,Valve aims to change that truism. Containing Portal, Half-Life 2: Episode 2, the long awaited Team Fortress 2, as well as gift copies of Half-Life 2 and Half-Life 2: Episode 1, The Orange Box is a full frontal assault on the notion that value packs belong in bargain bins.

Of the titles in The Orange Box, Portal has received, by far, the most media attention. Not only is the game itself stunning, the tale of its creation became an instant 'rags-to-riches' story when Valve snapped up Kim Swift and Jeep Barrett on the strength of their student project game Narbuncular Drop, a kind of proto-Portal. The story behind how Portal came to be, however, isn't half as interesting as the game itself.

To put it simply, at a time when retreads and sequels are the standard, Portal is something new, something fresh. Much has been made of the characters and mood of the game – glaDOS, the Weighted Companion Cube, that cake phrase you've probably heard quoted a million times by now – but that's not the important thing about Portal. It's adorable, and it's hilarious, but if that was all it was, we wouldn't still be talking about it. The thing to know about Portal is this: it will forever change the way you think about three dimensional space in games.

The portal mechanic – that of a gun that fires two linked portals, one red, one blue – is so ingenious, and so well implemented, that it may forever ruin you for jumping puzzles or platformers. You'll find yourself, in other games, looking at long lines of hovering platforms or a treacherous cliff side, thinking about how the whole thing could be bypassed with a couple portals and some clever use of momentum. By the end of the game, you'll be stringing together portals to vault up massive vertical spaces, and across impossibly wide chasms. Portal teaches you to interact with a first person game in an entirely new way. This is one of those rare games that you simply must play. To borrow the words of glaDOS, “This is a triumph.”

Unfortunately, I can't say the same thing about Episode Two. Instead, I can say this: it's more. More hours spent fighting headcrab zombies, more time spent in vaguely eastern-European wastelands, more boss battles, more driving. The driving, at least, is fun this time – instead of a stripped down, junker dune buggy, you're behind the wheel of a... stripped down, junker muscle car. While Forza may be in no threat from Half-Life's driving sequences, the car has a weighty feel, a satisfyingly beefy engine roar, and slews like a pig in mud when you spin it around to run over a zombie. Oh, and, of course, there's also more gravity gun. So much gravity gun, in fact, that two boss battles depend on it. A small one, first, to introduce you to the concept, and refresh your jump shot skills, and then, later, one of the most tedious affairs in boss fighting that I've ever come across in a game.

The final fight in Episode Two is a miserable plodding affair, combining the worst aspects of escort missions, driving mini-games, and boss fights. You fight off wave after wave of bosses, ten in all, each with mini-boss escorts, while trying to protect various destructible buildings, and keep them from getting close enough to blow up the one building that really matters. This wouldn't be so bad on its own – it's the stop-and-go nature of the fight, combined with the merciless repetition that really makes it unbearable. For each one of those ten bosses the routine is exactly the same. You drive to a base, collect a bomb, collect some health and ammunition, drive back to the boss, all the while hoping it doesn't get close enough to any of your buildings to destroy them, slam on the brakes, get out of the car, grab the bomb, and then fling it at the boss with the gravity gun. Of course, if you forget to kill the mini-bosses first, they'll shoot the bomb out of the air, and it's another drive back home to get a new bomb. If you miss, it's another drive back home, to get a new bomb.

Even worse, sometimes you can make a direct hit, and the magnetic bomb simply falls right off, after a two second delay, and it's another drive back. Of course, if you succeed and kill the boss, you're rewarded with... another drive back to fetch a new bomb. This exercise in miserable tedium is followed by what should have been one of the biggest dramatic payoffs in the series, but the placement of that dramatic event after such a miserable fight, combined with the way the writers all but sound an 'imminent NPC death' siren, combine to neuter the dramatic impact, leaving you unable to feel anything but relief that the whole mess is over.