Artifacts are born from dangerous anomalies that challenge our current understanding of nature. They sell for a few rubles, but their real cost is blood from the men who risk their lives inside of the irradiated Chernobyl exclusion zone in order to get them. A hostile place that breeds dangerous mutant and inspires even deadlier idealists and fanatics.
You can be one of these men, you can be a S.T.A.L.K.E.R. Good hunting.