A group of stalkers, for the first time, reaches the very heart of the Zone-the Chernobyl Nuclear Power Plant-and triggers a cataclysm on the brink of a catastrophe. An immense blast of anomalous energy transforms the Zone: the once reliable and relatively safe roads are no longer so, the landscape is wiped clean by outbursts of anomalies, and previously unknown areas appear on the Zone map. Stalkers and expeditions perish or end up isolated within the lost territories.
Clear Sky is what you should be playing when you want something as great as SOC and that's not SOC...
In spite of what many people say, Clear Sky is superior to COP in basically everything (gameplay, visuals, challenge, storyline, factions, upgrade system, relations, and amount of places to explore).
More of the same we saw in STALKER, only we get one new area in the beginning, it sets things up somewhat nicely you have very little reason to return... unless its to repair your armor and get upgrades.
Nobody seems to have any new missions for you when you come back, and the equipment sold by the traders don't have much interest once you have gone 1-2 hours into the game.
You do take different routes and only vaguely visit past areas, its more the same old stuff until you finally get to the bridge that takes you to Limansk.
Thats where things pick up and we go through a city like area. But once again we are treated to the same problems. Blocked off areas everywhere. This city is huge (according to the map) why limit where I can go? it all takes you unto one linear path.. everytime you take a detour you end up getting a blocked path and usually nothing to show for it.
For a game that seemed to emphasis exploration (STALKER SOC did somewhat though it still limited the areas in which you can go into another map) Clear Sky seems to have a even bigger aversion to it.
The story is barely worth mentioning.
Even with mods its barely worth playing if you've already played STALKER SOC.