Clear Sky provides a few improvements to the original formula, but at the cost of some frustrating mistakes.
Clear Sky is a Survival First-Person Shooter, which combines a variety of elements from both Horror and RPG genres. Your avatar not only shoots targets around, but also loots corpses, buys and sells equipment, talks to NPCs, upgrades and repair items, accomplishes objectives and freely explores the different areas of the Zone. Although your main objective is clear and very linear, your character can move around without a particular order, finishing missions and searching for important items during your travels.
If you played the first game, Shadow of Chernobyl, you'll feel comfortable with this prequel. In truth, GSC Game World tried to hear their fans and improve some features, although not everything in Clear Sky is necessarily better than the original game. At the first moment, the most obvious improvement was the graphics, which look much better in this prequel. Although the enhancement was nice for those with uber machines, the X-Ray Engine consumes much more of your hardware than ever. Luckily you can still use 'Static Lightning' setting and configure other video options for optimal performance, although you'll probably not enjoy one of the most important features in Clear Sky by doing so. In this game, the graphics play an important role, especially if you really want to enjoy the immersion. Looking to dread places and stormy skies never looked so good in a game before. The sunshine, shadows and lightning effects are also quite impressive if your video card can handle it.
The sound effects aren't any better than Shadow of Chernobyl, but that isn't a bad thing because the first game had excellent sound and music. It's so haunting, when you're wandering in a dark forest, to hear a mutant screaming and walking through the plants. You can hear every possible sound you would notice in real life, which is a very nice touch. Combine this with the incredible visual effects, and Clear Sky becomes one of the most immersive games ever released.
This prequel is obviously aimed to the fans, because the neophyte will feel overwhelmed at the very first moments of the game. First of all, after fifteen minutes or so, you're on your own. Your character can move around freely and you'll easily forget to accomplish a secondary mission or even the main objective, because there're so many things to do in the Zone. You can travel at every possible place, searching for important artifacts and equipment, probably left by an unlucky dead stalker. But be careful, there're mutants and lots of dangerous anomalies around. For instance, in an area full of wrecks, you may find something useful in a stash or so, but you may get irradiated if you don't have the proper equipment to enter in that particular area. Also, if you don't feel secure enough to walk on a given place, because your detector is warning you that there is an anomaly nearby, you may throw a bolt and see if you can reveal the trap. These kinds of little concepts are exactly the reason why Clear Sky is so immersive. Your survival instincts will be put to the test.
As a proof that this game is for hardcore players, you'll notice that GSC Game World was seriously harsh when boosting the difficulty here. The AI is extremely precise when shooting through obstacles and throwing grenades at you, even if it's damn dark; it seems that the weather effects simply don't interfere in the behavior of your enemies, although the player him(her)self will feel aimless in those situations. This is probably one of the main reasons why Clear Sky wasn't a hit as it should have been. However the most noticeable problem is the game's quality. The first version was extremely buggy, with random crashes, script breaks and performance issues. For instance, I noticed that my main objective got glitched when I was traveling between two areas, which made the mission impossible to be completed. Reloading the game had no use, and I gave up continuing playing until a decent patch is released. Then I tried the 1.5.04 version and still the game had serious issues around. It was only with the 1.5.07 version that I could keep playing Clear Sky decently, and I finished most of the game with this update, although I played the final sequences with the 1.5.10 version. After patching the game to the newest version, you'll have a fairly polished Clear Sky to enjoy.
Problems aside, GSC Game World is a real master when talking about variety. The game allows you to wander around freely, exploring abandoned areas to get special items, shooting at dangerous mutants and facing other hazards of the Zone. You can also join to several factions available, each one unique and with a different point of view about this amazing and unknown place. For example, Duty has a purpose on not allowing the Zone to expand its influence around the earth. These guys think that it's too dangerous to let the dangers spread out in the rest of the world. However an opposite faction, called Freedom, wants exactly the contrary. If the Zone expands to the entire earth, everyone would get the benefits that are only present in this hazardous place. There are rumors of artifacts that can cure diseases, as well another anomalies which would be extremely useful for the humanity. It's really up to you to decide what faction has the better reasons about the fate of the Zone, and you can join and betray them any time you want. There is also the option to not become part of any faction, so you can adventure alone seeking for glory on your own.
The real fun on joining to a faction is facing the opposite group while capturing points of interest. At random times, your faction tells you to help your teammates defend a particular place or attack an enemy outpost. Keep in mind that it isn't always possible to answer every call from your faction, so don't feel overwhelmed if you fail a mission. Another great benefit on working for a faction is to buy stuff that would be hard to find elsewhere, such as advanced weapons and upgrades. And if you ran out of money, you can always accomplish a side mission any time you want. As you can see, there are a number of possibilities in Clear Sky, and you'll sometimes forget to keep going on the game's main objective.
Unfortunately, GSC Game World made your encounters with the dangerous mutants very sporadic and even frustrating. I'll spoil a little to illustrate the problem: there is a cavern, known as the Poltergeist Cave, which would be extremely captivating if only you could get lost or trapped in there while trying to find a special artifact. In truth, you just enter the cavern, kill some bandits, avoid a few objects thrown at you and get the artifact. You see, it's totally different from that creepy laboratory from Shadow of Chernobyl. On the other hand, traveling in the Red Forest at the night is extremely immersive; after you walk a few meters away from the main road, you'll hear chilling sounds around. I remember I was walking slowly, trying to notice a visual distortion at some particular spots, which would mean that there is a Bloodsucker sneaking around. There're no words to describe how haunting it is to visit that creepy forest.
Unlike the first game, Clear Sky allows you to choose your favorite weapon and keep it forever if you want. Your weapons still deteriorate, and they jam more frequently as their quality goes down; but this time you can just go to a technician to fix your equipment. This is particularly important for combat suits, because their effectiveness to retain the different sources of damage is reduced. The tech guys also allow you to improve your gear for a price, although certain upgrades are only available if you find the flash drive with the upgrade data. This makes exploration even more important, since you can make your weapons and armor really powerful. I chosen an assault rifle as my main weapon, and I upgraded my gun enough times to make it an awesome tool of destruction; I boosted its precision, stability and made it lighter to carry.
A number of features in Clear Sky make the firefights in this game quite impressive. You can use pistols for light-armored opponents, heavy shotguns in close combats against mutants or assault rifles when facing the dangerous Military and Monolith soldiers. But the game doesn't allow you to move around with lots of different weapons, because you get encumbered depending on how much weight you're carrying in your inventory. It's better to choose two or three weapons and upgrade them to use in different situations. It's also possible to load your gun with special bullets, which can pierce rough surfaces and kill your opponents faster. The special ammo is so important that I had to stop for a while and do some side quests, so I could get the amount of money to spend in piercing bullets for my modified assault rifle; this is very important later on in the game.
Your armor can also be upgraded to get more protection against the different types of damage, or to make your suit lighter and even increasing your weight capacity. It's also possible to boost your defenses with the artifacts, although they're quite sparse in Clear Sky and very hard to spot. Unlike Shadow of Chernobyl, this time you must use a special device, like a detector, to search for artifacts. They're mostly hidden between dangerous anomalies, and getting them is so difficult and boring that I rather preferred to not waste my time doing so. In the first game, looking for artifacts and combining their bonuses was very important and fun, but in Clear Sky I simply ignored their existence.
The replay value in this game is quite good, but not as much as in Shadow of Chernobyl. Maybe because the mutants aren't very present and there is just one possible final. However the absence of multiple finals was probably the best choice, considering how Clear Sky ends to better explain the genesis of the original game. Naturally, you have a good reason to replay this prequel because you can raise (even more!) the difficult level and try the different factions that occupies the Zone. Considering the events in Clear Sky are mostly random, you will hardly experience the same thing after restarting the game.
The multiplayer is quite simple, but it's there to extend the life of Clear Sky. As I keep saying, a cooperative mode would be nice. I can't imagine how fun would be to venture in the Zone with some buddies, planning the best way to capture an outpost or how to defend ourselves against an enemy invasion. But the competitive modes are fair enough, pretty much the same as the ones featured in Shadow of Chernobyl. Since I tried only the deathmatch mode two times, I can't say much about the multiplayer experience. From what I could notice, in the 1.5.07 version it works quite well.
S.T.A.L.K.E.R.: Clear Sky shows that improving a game isn't an easy task. GSC Game World brought some nice concepts to the series, but they also made a few things worse than before. Maybe with a little more beta testing, more mutants to fight against and a few improvements to the key features, Clear Sky would be the best modern game ever released. Who knows they can achieve this in Call of Prypiat? Just don't forget to design women models this time...