What I still remember from MoS, what really stands out (it's been a really long time so I have only a vague recollection overall) , was the atmosphere. There was just something about the feel of the world that really clicked and everything just seemed... real? Instead of being just a stage for the story and puzzles (as many games feel). Of course the usual lack of people (which is common for most games, you just can't make a realistic amount of people (who act realistically) without making the game excessively heavy for also those with a slower hardware) did take away the usual bit but it doesn't really matter that much and there were the occasional scenes such as the poolside in the 'station were just inexplicably atmospheric (or something - I mean I still think back sometimes on the pool and think what an awesome feeling there was, I just can't explain why
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