Half Life 2 Game Review - a retrospective

Half Life 2 Review

Back at the end of 2004 one of the most awaited games for PC ever was finally released. Delayed for a year due to a security breach and early problems with the Steam download and registration system, its arrival was anticipated by gamers for nearly two years. Half Life 2 made almost as big an impact as the original. Read why in the rest of this article.

A Hard Act to Follow

The original Half Life game shot to a massive success without having to rely on a massive hyper-marketing machine. The ingredients for success were a solid FPS game that added cinematic elements and new kinds of experience that reached beyond the staid key collecting 'puzzles' that had been the mainstay of the genre since Doom was released in 1993.

At its heart the sequel has a lot in common with the original at the technical level. It uses an evolution of the Source engine that Valve originaly created for Half Life 1. New systems have been added to render more elaborate geometry in the landscape (displacement grids), and the character animation system has many new features. The most obvious visible changes are in the kinds of special effects the engine can produce, making good use of the shader hardware of modern graphics cards.

While the original game made good use of TNT2 class hardware, the newer incarnation supports the power of the latest graphics cards. This allows Half Life 2 to render a lot more polygons in a scene than the original, and to use much higher resolution textures. The difference is instantly obvious. However, one of its great achievements is to provide workable fallbacks so that slower, or less capable cards can still render the game at a good speed. Much to my surprise, I found that I could play Half Life 2 perfectly well on an old GeForce 2 card when a mains spike proved to be the death of the ATI 9800Pro that I was using at the time the game launched.

A Dark New Future

The original game created a coherent and detailed setting, but didn't provide much in the way of back story. In Half Life 2, things are different: not only is there massive, well realised setting, filled with different characters, but many mysterious events have taken place since the end of Half Life 1, when Gordon accepted the G-Man's offer.

We aren't told what Gordon might have been doing since the end of HL1, indeed, for all we know he has been frozen in stasis, or sent forward in time immediately from the end of HL1. Gordon as ever is uncommunicative, and doesn't speak a single word throughout the game. The end result is that you as the player never learn what has happened to him between the games. However, the game characters are quite eager to tell you what's been going on in their lives since the original Black Mesa incident.

Though it's obvious at the start that you are entering a dark dystopian future that borrows heavily from Orwell's 1984 and the bleaker fictions of Philip K Dick, with a healthy dose of 'homeland security' thrown in for good measure. Later on, War of the Worlds and Arthurian legend start to show their influences. In the end HL2, despite is numerous and obvious inspriations, creates such a dark and potent mix of elements that it becomes a unique entity that fuses themes and ideas in a way that will be emulated for years to come.

The powerful emotions that the sinister setting conjures up bring meaning and interest to the story, even when Gordon's own involvement remains extremely simple. The last remnants of humanity battle against an oppressive regime, ostensibly run by collaborators, but in fact run directly by the sinister alien forces that act as puppet masters for the wretched 'leader' Doctor Breen. That the aliens are called 'the Combine' only enhances the idea that they are a monstrous force whose only purpose is to harvest and consume life on an enormous scale.

The actions of the various characters that Gordon meets reinforce the idea that he is an important individual of heroic import, and this helps to provide a sense of satisfaction with and recognition of the player's achievements as progress in made through the game. The presence of the G-Man, hints at the possibility of an ultimate future victory, or at least a slender chance to fix what went wrong.

In short, should Gordon's quest prove unsuccessful, humanity will be methodically destroyed and modified into a servitor race for the enigmatic forces of the Combine that have invaded the earth. As Gordon Freeman you must repeatedly achieve the impossible, and of course you succeed against tremendous odds, which is extremely satisfying.

Game Play

When it comes to game play, HL2 is outwardly very similar to HL1. However, things generally move along more quickly with a greater density of new experiences. You don't have time to become bored of an area before it's over and you're on to something new.


The weapons are somewhat different from the original, but ultimately most of them work much the same way. The 'bug grenades' of the original are missing, and instead you get a pheremone producing stress-ball that summons vicious alien ant-lions to attack your enemies. The weapons of HL2 are overall more satisfying to use than those of the original. The Combine Overwatch Pulse Rifle is particularly effective in most situations, and a SPAS-12 shotgun does the job close up. Ammunition is rarely in short supply, though quarrels for the sniper crossbow are hard to find through much of the game, pushing you towards more confrontational combat than sneaky sniping. Magnum ammunition is also reasonably scarce, presuambly as it can also be used effectively for long range sniping.

Unlike HL1, you have access to two vehicles during the game. These are also (eventually) fitted with weapons that have limitless ammunition and the buggy also provides a supply of ordinary bullets. The boat's weapon can only fire for a short time without running out of energy, you then have to wait a short time for it to automatically recharge. Tapping fire instead of holding it down solves the problem and increases accuracy as well. There is less restriction on use of the buggy's weapon, but it is not used in the same kind of grand set-piece encounters.

The Zero Point Field Manipulator

The gravity gun is one of the innovations in HL2 that lets you magnify your ability to interact with objects. With the gravity gun you can lift heavy objects as well as hurl things about at great speed. You can use it to catch barrels that zombies hurl at you, or catch grenades and throw them back at your enemies.

The gravity gun is flexible, but not overpowered. Unlike the teleport gun from Unreal Tournament, it isn't a tool that completely dominates the entire game. It's rare to use the gravity gun directly in combat, and it remains most useful for puzzle solving. You can use it in certain settings as a weapon replacement, but it's always difficult enough that you are unlikely to bother unless purely for fun or to save ammunition - which isn't usually necessary. For example, it's possible to complete 'We don't go to Ravenholm' using only the gravity gun, but there's no need to do so unless you find it amusing.

And then there's the end of the game, but I'm not going to spoiler it...

Problem Solving

Half Life 2 never bores you with pointless key quests, and only on rare occasions do you have to trek miles to activate a switch that opens a door in some other equally remote location. Instead is delays you with a wide variety of physics based puzzles. In this regard HL2 finally delivers what we have been promised in games for so many years: real physics. While the game's physics system has some weaknesses that might have been improved with further tweaking, it works well enough for you to do all kinds of semi-realistic things.

Many of the 'puzzle' solutions are extremely obvious, but in the context of a computer game are completely novel. They range from the most basic idea of throwing things into shallow water so you can get across without being electrified, to elaborate set-ups with exploding barrels, cranes, swinging girders and great big pieces of engineering. In the zombie town of Ravenholm there are a number of elaborate contraptions that you can use to get around, kill zombies or yourself.

An early version of Ravenholm featured in the Trap Town demo, and the physics features there are directed more towards combat situations than puzzles. Nevertheless, the amusement to be had from exploring the physics system there, and hurling giant circular saw blades into hordes of zombies, is substantial.

Occasionally, the game misses a chance. For example, there are hard to reach areas, and difficult crate stacking tricks that are rewarded with nothing, or a swift tumble out of the game-world followed by a reload. Given the other features of the game, it would have made sense for a much richer set of secret weapon caches and small prizes.

Through much of the game there are many non-secret secrets: where a spray painted logo directs you to an easy puzzle that gives access to a weapons cache. This provides a sense of achievement for even the laziest explorer.

Unlike HL1, there isn't a tedious jumping puzzle section in the middle of the game. Though there are some awkward areas to navigate, there is never an area where navigation is a substantial obstacle. I heartily condone this approach: while jumping works well in side scrolling platformers and acceptably in the gridded world of the old Tomb Raider games, it does not work well in genuine first-person games. The facts that you can't see where you're jumping from, that you can't judge distance properly, and that your direction of movement and view must remain the same (bar strafing) combine to make first person games that try to add jumping puzzles very unpleasant indeed. When they showed up in Doom 3 I turned it off and never looked at it again.

It's not a movie, it's a game

One great thing about HL2 is the complete absence of pre-rendered cut-scenes. This is something else we were promised by game-developers about six years ago. While there are some parts of the game where you are forced to listen to a character provide some exposition, you don't have the situation where the game is continually interrupted and stopped when the action should be at its most frantic. Nor is there ever a graphics gap between what you get in the game, and what you get in the cut-scenes.

By slipping some short sections of exposition into the game, the story is kept clear enough, and there are only a few spots where upir freedom is limited so that a character can talk to you. At those points you get a longer scene, but you never break out of your first-person view point, Gordon never speaks, and you usually retain control of your character. The section with Alyx where you go to play with the giant robot Dog works particularly well, with her slipping in a few words of dialogue here and there as you move through the level. It always feels like you are living the story, not like you are having it told to you.

The game lets you actually play through the 'best bits' rather than showing them to you in a movie. For example, you have complete freedom in the boat chase along the canal where the Combine helicopters are continually attacking you and dropping in troops, ambushers are pushing fire barrels in your way, and you are hurtling along, driving flat out over jumps and through pipes. Many other games take that sort of action away from you and make it into a movie. In HL2 you get to play all the best bits of action without the camera ever pulling away, the screen narrowing, the controls freezing and the narration kicking in.

By using the game-engine to do the limited amount of pre-determined story telling that the game requires Valve also saved themselves from making multiple models of the characters, avoided issues with movie compression, and saved a lot of data space on your hard drive that would otherwise be wasted on movies you'd normally just skip through anyway; a lesson that Sony Online Entertainment could do to learn.

The facial animation system for the characters is excellent. While Final Fantasy X made the first decent use of this type of approach, HL2 perfects it. There was never a time that I thought I would rather have a hand-animated pre-rendered model rather than one of the real-time in-game models in HL2. The facial modelling is such that the character's mouths don't make odd shapes, and their faces don't crack or warp strangely while speaking. HL2 is also one of the few games to avoid the 'dead eyes' syndrome, where insufficient reflection from the character's eyes creates the impression of looking at a corpse (Unreal II provides a good example of this horrible effect).

It's notable that the excellent Vampire: The Masquerade - Bloodlines game by Troika used an intermediate version of the Source engine to build an entire RPG with hundreds of conversations and detailed characters. Barring the fact that their models weren't always as well made as the ones in HL2, it was an impressive result. Unfortunately, bugs in their game damaged its sales, though the worst were patched before Troika finally went out of business. Despite its flaws, VtM - Bloodlines was an innovative game with many endearing qualities, delivered some of the best fights in an RPG, ever, and is a better stealth-em-up than most dedicated stealth games.

So what about the game levels?

Some criticism has been levelled at the linearity of HL2's game levels. I think this is largely unjustified, particularly when it comes from people who in the same breath wax lyrical about Doom 3. There are few FPS games indeed that aren't linear, and most of those that aren't strictly linear but just use a hub-system that exchanges strict linearity for strict linearity plus tedious backtracking.

I would prefer to describe HL2's levels as 'tightly focussed' rather than linear. When you throw in the more complex scenarios, such as the spots where you have to defend an area, or survive waves of attacks, and the levels rarely feel linear. In practical terms it's not a reasonable use of resources to make an FPS game that offers multiple paths through every area, and different solutions to every problem. Even classic RPGs like Fallout didn't succeed completely at that sort of approach, and they had a much richer palette of possible activities to work with.

The only way HL2 could obviously have offered more options was to add a stealth dimension. Negotiation was never going to be an option with the Combine. Interestingly, one of Doctor Breen's comments refers to this, noting that Gordon has not had time to develop his stealth skills since the first game. Is this a hint that future Half Life games may offer considerably extended stealth options? I'd love to play a Half Life with a seamless mesh of stealth and combat: a game the way Metal Gear ought to be. Ghost Recon did something towards offering this, but it has left the PC for the consoles and is unlikely to return.

The amount of variety and the range of completely different challenges that the game levels offer far outweighs any niggling complaints about their traditional linear structure. You've barely got the hang of avoiding Combine troops before you're racing the air-boat, and by the time you've mastered the boat you're back into heavy combat against increasing numbers of enemies. You have time to pause and play with Dog while Alyx, Eli Vance and Doctor Judith Mossman bring you up to date on past events. An adventure in Ravenholm sees you slaughtering zombines and dodging headcrabs, but you quickly move on to shooting more Combine, ant-lion antics and then buggy driving, and so on...

The game never lets up with the changes in setting and variations in the types of enemy and degree of threat you have to deal with. Some areas require careful exploration, others are a flat-out battle from start to finish, and some quiet spots can become very active very quickly when the alarms go off.

The artwork

The designs in HL2 are a strange combination of the extremely realistic and the unashamedly futuristic. The gritty, dystopian City 17 contrasts with the ocean views of the coastal road and the dark sci-fi interior of the Citadel.

The air-boat and buggy have a distinctly Mad Max feel about them, though I thought some of the tubual steel the buggy is made from looked too thin to be realistic. That was a rare failing in the graphics, which are generally highly detailed and realistic. It looks like the Valve art team went on a bit of a jaunt around Eastern Europe to get ideas for their designs, and cyrillic lettering and communist style concrete tower blocks are commonplace elements in the setting they've created.

One thing that HL2 does better than any game before it is cables. There are cables and wires everywhere. They hang between poles, are hooked between buildings and dangle across gaps and out of fissures. They aren't just static decorations, they're real physics objects that move about as you move the things they're attached to. You can even find yourself running about on them on rare occasions. While cables (and chains) may seem like a minor thing to have in a game, they add a new level of realism to many of the areas. Once you start to notice them in HL2 you also start to notice how they are missing in so many other games.

The character models are extremely well made, and the designs are good, though perhaps a little obvious. The inclusion of a 'tough black woman' character in the form of Alyx seemed a little too calculated a decision. I suppose we should be thankful we didn't get one of the dull, shallow cliche characters that populated Unreal II or Doom 3. Let's not forget that on the up side, the model of Alyx looks excellent and has very believable facial animation. I recall when the game launched there was endless demands for porn mods and a naked Alyx on the forums. I'm not quite sure why. It's not as if she appears to be designed as a sex object: very strange.

Despite the top notch visual design, the character of Alyx did feel like one of the obviously contrived characters that Hollywood is always writing - from a world where a woman can't ever seem to join the police unless her father was a decorated officer who died in the line of duty leaving her with several barely suppressed neuroses. Or where it's impossible to be some kind of medium without having a mystical old grandmother who taught you wisdom beyond your years and gave you the moral strength to only use your powers for good.

Doctor Breen's character model is also very well made, and the other major characters like Judith Mossman and Eli Vance are all of a high standard. If there's a character complaint it's with Gordon himself: we never get to see him. Unlike the protagonist of Doom 3, he lives in a world that seems reluctant to provide him with a decent mirror. This seems unnecessary, as there are so many images of Gordon outside the game that Valve can hardly argue that seeing his face breaks the game experience somehow.

The bad guys, mainly in the form of various Combine troops look approriately grim and remind us of the real world and the real terror states that are growing up around us. Perhaps it is in the glassy lenses of the Overwatch respirators that the game comes closest to conjuring real darkness and horror. The sci-fi visions of Cthulhoid aliens sucking our oceans dry and poisoning our atmosphere are dark enough, and allude just as much to real-world horrors that face humanity - but the vision of a state where order is maintained with check-points, beatings, tear gas and bullet strikes a lot closer to home than the large scale menaces of pollution, industrial poisons, global warming, climate change and the like that are rolled up into the Combine metaphor.

The nightmare world that is so excellently realised by the Half Life 2 artists creates a much more powerful sense of real evil and horror than anything in schlock shock games like Resident Evil or Silent Hill. HL2 raised the bar for realism and immersiveness in an FPS and for the moment there are no obvious contenders. By comparison Far Cry looks like a flashy shader demo, and Battlefield 2 looks like a giant playground full of giant military toys, otherwise barren. Doom 3 did a fantastic job of looking like a set from Aliens, but it was never even trying to be realistic and there seems something almost kitschy about its cartoon style compared to HL2.

Sounds good but not great

The sound in Half Life 2 is alright. It works. Guns go bang. The only really good sound is the air-boat, which is amazing. The chatter of the troops' radios is a nice touch, but becomes repetitive. The character dialogue is fine, but if I recall, wastes far too much space because it isn't compressed. That the game doesn't use compressed audio by default for such things is simply baffling, and poses an obstacle for anyone who wants to use the engine for other purposes.

Overall, the sound is the weakest area of the game. There are times when it works reasonably well, but it's never so good that you can't live without it. I know several people that played the entire game with it turned off because they found it 'distracting'. It's a pattern with games in general that sound is overlooked, given a low priority during development and is the last thing to receive attention. It's a pity. When you compare great movie soundtracks with awful television scores you can easily appreciate the difference good music and clever use of sound make to a production. The first Resident Evil movie made unparalleled use of sound in a horror movie. Even though you knew exactly where most of the jumps were coming, you still jumped: you couldn't stop yourself. This is an area where even Silent Hill edges ahead of HL2 in terms of production quality.

It's time we had games that sound as good as movies, and it seems we're still a long way off. It's ironic that we have so little problem actually playing back high quality sound: sound as good as you can get on a big budget movie. We can't render visuals as good as a movie, but most of the development effort goes into visuals. We can play movie quality sound, but most games just play basic sound effects and stick an vaguely inappropriate, badly mixed sound track over the top, with little regard to what's actually going on. It's clear that some effort was made with sound on HL2, but it wasn't given the level of attention and investment it deserved.

Half Life 2 could have gone a lot further with sound than it did, and a game that is of such a high standard elsewhere let itself slip. Still, that air-boat does sound better than the vast majority of racing games.

Mod Scene

The vast number of HL2 related fan web sites seem mostly to do with modifying the game engine to do something else. Because Valve have thoughtfully provided a full set of tools for development and modification of the engine, HL2 is one of the best choices of game to work with if you want to create 'hobby' content.

The Source engine's source code is fairly easy to work with, and once you are past the obstacle of actually building code that links, it's a small step to make interesting modifications to the code. Meanwhile, almost every existing art asset and sound from the game is available for you to use in your own levels.

The documentation for the Hammer editor leaves something to be desired, though third party efforts cover most of the things you would want to do. There is still a lot that remains unexplained, or only partially understood. If you create something and it doesn't work, it's often very hard to work out what the problem is.

The Hammer editor itself is not the best tool to work with. You really need to create your own custom asset directories or otherwise you waste a lot of time searching for what you need. The 3D editing facilties are weak, and doing anything with sloping surfaces is a tedious and awkward process. The brush based BSP editing style is old fashioned, and unworkable for detailed elements. Trying to model detail into the brushes results in slow and unweildy levels that take forever to compile. An alternative exists, in that you can import pre-fabricated models made in other 3D packages. However, the lack of a properly supported 3DS Max exporter is a continual source of problems.

The pre-fab approach is also quite art intensive and time consuming. Each object has to be custom built, and is rarely reusable. The first few times you try to import an object you will undoubtably encounter scale issues, and when building into complex arrangements, it's often infuriating that you can't import the level into Max so you can position and scale properly before exporting.

Valve themselves suggest a Maya based tool, which you can download for free, as your 3D modelling solution. However, if you are not a paying member of FilePlanet, your chances of ever managing to download it are either slim or fat. The tool should have been part of the Source engine and downloaded through Steam if it was expected to be any sort of standard.

These obstacles aside, the HL2 engine lends itself to a wide variety of modifications and can be used to create many sorts of game with a litte effort. However, it is not a universal engine, and has many limiting factors. The same could be said of Unreal II, etc. but marketing spin tells another story. It's possible to try out Source for free, and I strongly recommend that developers do so before getting involved with Unreal.