Just like the original game Metro 2033, Metro: Last Light is played from the perspective of Artyom, the player-character. The story takes place in post-apocalyptic Moscow, mostly inside the metro system, but occasionally missions bring the player above ground. Metro: Last Light takes place one year after the events of Metro 2033, following the canonical ending in which Artyom chose to proceed with the missile strike against the Dark Ones (this happens regardless of your actions in the first game). Redux adds all the DLC and graphical improvements.
Quality-High, SSAA-off, Texture Filtering-16x, Motion Blur-Normal, Tessellation-Normal, Advanced Physx-off.
At Ultra HD 4k we see the advantages of spending a lot more money. Not everyone needs (or wants) a 4K resolution however.