Question 1

Is Anomaly free?

Accepted Answer

Yes. It is a free community standalone distributed via ModDB.

Question 2

Do I need Call of Pripyat?

Accepted Answer

No. Anomaly is standalone — no GOG purchase is required.

Question 3

What is GAMMA?

Accepted Answer

G.A.M.M.A. is an optional hardcore survival modpack for Anomaly (https://github.com/Grokitach/Stalker_GAMMA). PlayBound lists it as the GAMMA edition — install clean Anomaly first, then the official G.A.M.M.A. launcher.

Question 4

Is GAMMA under Call of Pripyat?

Accepted Answer

No. GAMMA requires Anomaly. The CoP page is the paid GOG campaign only.

Question 5

How big is GAMMA?

Accepted Answer

Plan for a large download and tens of gigabytes free — often on the order of 80–130 GB depending on options and updates. An SSD helps.

Question 6

Does S.T.A.L.K.E.R. Anomaly have multiplayer?

Accepted Answer

No. S.T.A.L.K.E.R. Anomaly is a single-player game, so there is no multiplayer mode to join or host.