Yes, you can safely buy Gray Zone Warfare, or its DLCs on some key reseller sites. We are partnered (directly or indirectly) with the sites listed below. This means that when you purchase a game key on one of these sites, you can be sure that the key comes from MADFINGER Games.
You may find the game listed on sites other than those listed below. In general, we don't recommend buying the game outside of Steam or the partnered stores, as we cannot guarantee the validity of those keys.
The list of partnered stores:
2ZPlay
3Kropki
5Deniz
Ananda Digital
BeCharge
Colby d.o.o
Culturel Ludique Divertissement
Dukesy Limited (Dload)
East Caravan
Electronics Boutique Australia PTY Ltd
Fanatical
Gamefinity
GamersGate
Games Republic
Games2Egypt
GB Digital Distribution OÜ
H2Interactive Co., Ltd.
Heybox
Humble
Indiegala
JoyBuggy ApS
MacGameStore
Metaboli S.A.
MGM Bilgi Teknolojileri A.S (Oyunfor)
Mikhail Tsyrulnikov (Gameray)
Neuvee
Noctre
Planet Play (Sphaira Innovation AG)
PlayAsia
Playsum Inc
Softflix AG
VoidU