Each of the main factions provide services, most importantly access to a trader and an engineer. The player character is a mercenary, and may do missions for any faction or remain completely neutral without disrupting the necessary progression of the game.
The stronger a faction becomes, the better equipment the traders can provide and their soldiers can use. The player will be able to join and help factions in their battles. Different factions will struggle for territory, attacking to gain territory and then defending to keep it, while others then try to retake it. The most significant gameplay addition since Shadow of Chernobyl is the faction wars system.
This game combines elements of first-person shooters ('twitch-based' aiming, with a first-person perspective), survival horror (ammo-scavenging in a frightening atmosphere with powerful monsters), and role-playing games (inventory management, quests, character interaction, armor types, and defense stats). S.T.A.L.K.E.R.: Clear Sky is a first-person shooter, survival horror video game with role-playing elements developed by Ukrainian developer GSC Game World and published by Deep Silver in 2008 as a prequel to S.T.A.L.K.E.R.: Shadow of Chernobyl.
