The problem was that Clear Sky was buggier than anything ever released.
3 patches in less than 3 weeks? I mean come on!
I played Shadow of Chernobyl and it wasn't anywhere near as buggy as Clear Sky.
Clear Sky was also highly disapointing in the fact that 80% of it was Shadow of Chernobyl again. Same maps, same NPCs, same enemies, same weapons (for the most of it), same anomolies etc. While it did add some new gameplay elements as territory control it was extremely poorly implemented in reality.
Extremely lackluster linear ending (Shadow of Chernobyl had like what? 10 endings?) coupled up with a storyline that to me made no sense with Shadow of Chernobyl just made the entire experience mediocre and questionable if it can even be called a sequel/prequel at all.
It is really sad concidering I really loved Shadow of Chernobyl and I concider it to be one of the top 5 best FPS of all time.I rarely replayed a game so often as I did with Shadow of Chernobyl.
In my opinion - while it might sound harsh, Clear Sky should have been nothing other than a DLC for Shadow of Chernobyl. At least then the thing would have bloody worked without crashing all the freckin' time.