The 20 best deals in Valve's massive Steam sale

Steam is in the midst of an unprecedentedly huge sale . Literally hundreds of games have become stupidly cheap for ten days - too many to easily keep track of. I'm the kind of gamer who's actually bought things he already owns on Steam, just to have them on Steam, so I've been poring through all the offers to find the best. There are some clear winners, some absurd bargains, and some fairly obscure gems that are now close to free. These are my twenty picks of the best, cheapest stuff. Today's deals will only last till 6pm BST, 1pm EDT. The rest are all good till July 4th.

Today only

Civilization IV : £3.24 - expired

Surely the least you can pay for the most ruin you can cause to your personal life. A pittance for the pinnacle of a famously addictive turn-based strategy series.

Max Payne 1 & 2 : £2.49 - expired

They're actually only £1.50 each, but they're both great so what the hell - save the 50p. It's the definitive diving-sideways in-slow-motion firing-two-guns while-wincing game, dressed up with pulpy melodramatic narration and comic book panel storytelling. Max Payne 2 in particular is a genuinely superb shooter, still slick and decent-looking today. If you want a taster of the marvelously purple prose, you don't need more than this Penny Arcade .

Flotilla (78% in PCG UK): £1.75 - now £3.49 (still worth it)

Genius spaceship combat game, all about positioning your small band of ships strategically in true 3D space, to pound your enemies' undersides. Playable - and brilliant - in co-op, and dramatically reduced today.

Half-Life 1 : £1.19 - now £4.01 (still worth it)

Yeah, okay, you probably have it. But just in case you don't, a quid for the game we gave our joint highest score ever is just kind of mad. It defined a generation of cinematic storytelling in action games - a generation that mostly failed to do it even half as well.

Ridiculously good bundles

THQ Complete pack : £26.49 - save £231

Just a crazy amount of really, really good games in here, a lot of which got overlooked on PC. It includes all three Company of Heroes games, the first of which is still one of the great RTSs of our time. But it's also overflowing with really diverse, fun experiences: the horrific Metro 2033, the superb and completely destructible open world sci-fi Red Faction Guerilla, the moody original STALKER, the gloriously silly Saints Row 2, the beautiful Diablo clone Titan Quest, the mighty action RTS Dawn of War 2, and the best of the previous Dawn of War games: Dark Crusade.

Introversion Complete pack : £5 - save 80%

Oh come on. FIVE POUNDS for everything Introversion have ever done? They have a knack for picking a unique concept, being incredibly smart about what the mechanics should be, and true artists in making them fun, and beautiful. Hack banks in the cruelly tense Uplink, conquer gorgeous polygonal archipelagos in Darwinia, steal a giant gold statue of the Companion Cube in its multiplayer cousin Multiwinia, and plot global thermonuclear destruction from the safety of your war room in the most paranoia-inducing strategy game: DEFCON.

Valve Complete pack : £35.50 - save £122

Crazy talk. By rights you should already have these, but for anyone who's resisted, you're not likely to have a cheaper way to snatch ten of the best games ever made. If you already have or don't want the Left 4 Deads, grab The Orange Box for £10.69 , and Half-Life 1 for £1.19 (today only) - the only big thing you miss with that much cheaper combo is Counter-Strike Source.

id Complete pack : £18.99 - save £105

Like Valve, id don't have the sheer number or diversity of some of the publisher packs here, but this price is just idiotic. You're getting what's still the definitive pure multiplayer shooter with Quake 3 Arena, a classic whose wonky mix of the arcane and the sci-fi is still fascinating with Quake 1, and a slick but old-school horror shooter with Doom 3. You also get all the old Raven classics - I'm incredibly fond of the fantasy-Doom vibe of Heretic, and even its true 3D sequels Hexen and Hexen 2.

Square Enix/Eidos complete pack : £67.49 - save £370

OK what. You save three hundred and seventy pounds? There's just too much in Eidos's incredible history to wax lyrical about each highlight, so I'll do the quickest breakdown I can:

Batman: Arkham Asylum: near-perfect punching, brilliant stealth.

Deus Ex: genuinely and honestly the best game ever made. Here's why .

Hitman: Blood Money: dark, open-ended and phenomenal, I've played every mission twenty times and I never run out of new ways to orchestrate horrific assassinations.

Just Cause 2: the most gorgeous and liberating screw-around game I know of.

Supreme Commander 2: after a heavy AI overhaul, now one of the best strategy games of our time. We still play it almost every lunchtime.

Thief: Deadly Shadows: contains one of the most unforgettably terrifying levels in gaming - unmissable.

Tomb Raider Legend, Anniversary and Underworld: wonderfully relaxing, beautiful adventures for rainy sundays.

Individual gems

Splinter Cell: Chaos Theory : £6.02

Still the best Splinter Cell - thoughtful, violent, perfectly paced, and with an unrivaled co-op mode.

Prince of Persia: Sands of Time : £6.02

The latest in the series is a decent attempt to basically remake it, but Sands of Time is still the best of the fluid 3D platformers.

Beyond Good & Evil : £3.34

If no-one's gushingly recommended this to you yet, you haven't talked to enough game journalists. A sweet, exotic, and unique adventure as a heroine with green lipstick and a big hitting stick.

Rainbow Six: Vegas 2 : £6.69

If you want an idea of what Deus Ex: Human Revolution is going to feel like to play, play Deus Ex. Then play this. It's a showcase for a near-perfect cover system: first-person for shooting, third-person for hiding. And it's probably the best close-quarters tactical shooter around.

Dark Messiah of Might & Magic : £4.01

Here's what you need to know about the first-person fantasy fighting game: there are spikes, traps, ledges and breakable objects everywhere. You can kick people. And if you kick someone when they're near one of these, the game actually makes them fly a little further just to be sure they'll meet the stickiest possible end. A great brawler with some lovely physics-driven magic.

Space Rangers 1 & 2 (79% and 88% in PCG UK): £4.75

Brilliant yet sadly overlooked space adventure: you're a tiny ship scooting around the galaxy from a top-down perspective, tangling with other rangers and making a fortune for yourself. To get a sense of the fun you can get up to, you should read our friend roBurky's superb Space Rangers 2 diary , of his quest to, basically, kill everyone.

Far Cry 1 : £3.34

I still love the first Far Cry - it's just a blissful holiday in a beautiful nation with hilariously angry mercs trying to ruin it, and a wonderful degree of tactical freedom in how you shoot them all in the face.

Plants Vs Zombies : £4.89

PopCap's best game, and the first to really show they can apply their infuriating knack for addictive mechanics to a genre close to hardcore gamers' hearts: games in which you must kill zombies to survive.

King's Bounty: The Legend (88% in PCG UK): £2.49

Brilliant little RPG/turn-based-strategy hybrid. You trot about a pretty fantasy landscape on your horse, then when you run into a horde of horrible monsters, get your inexplicable army out from wherever they were hiding and fight it out turn by turn. You can conquer whole countries and set sail for new ones, increasing your army as you go.

Osmos : £3.49

Bloop. You're a blob of viscous stuff swirling around space with other blobs. You can only move by spitting out a part of yourself, to propel you in the opposite direction. Hit something bigger than you, and you'll be absorbed into it and lost. Hit something smaller, you'll consume it and grow. The levels start simple, then start asking you to get big enough to consume planet-sized enemies, or cast you into a beautifully swirling vortex of other blobs. Gorgeous, soothing and fun.

Galcon Fusion : £3.49

Strategy at its simplest: you have a number of ships, you can send them between planets, and if you've got more than the enemy has there, you'll win. Bigger planets build your fleet faster, and for the basic modes, that's pretty much it. Yet it's weirdly compelling, and surprisingly nuanced. Stripping out all the faffing with unit types and resources lets you focus purely one where to hit and how hard, and the numbers of ships involved can get hilariously large.