post-apocalyptic setting, underground metro, Moscow, atmospheric lighting, gas mask, military gear, survival horror, stealth gameplay, mutated creatures, desolate landscapes, abandoned stations, grimy tunnels, rusted trains, protagonist Artyom, first-person shooter, scavenging for resources, eerie soundtrack, dynamic shadows, narrative-driven, moral choices, radiation hazards, faction warfare, dilapidated architecture, immersive experience, detailed gun models, scarce ammunition, flashlight beam, cobweb-filled corridors, intense firefights, NPC companions, moral system, 3/4 view, soft ambient light, high contrast, detailed textures.