S.T.A.L.K.E.R. G.A.M.M.A. -- бесплатный мод от Gog

[SerW]

https://www.gog.com/en/game/stalker_gamma.
To play this game you also need
You must own ONE of the following games:

S.T.A.L.K.E.R. 2: Heart of Chornobyl - Standard Edition

OR

S.T.A.L.K.E.R.: Call of Prypiat - Enhanced Edition.

И вот еще один мод: https://www.gog.com/en/game/stalker_anomaly.