The game uses the Marmout engine to render hundreds of enemies on screen at the same time. This is best exemplified when the Union Army faces the Confederate Army at Antietam and many soldiers are on screen firing at each other. The animations are very basic in these large battles and most of the soldiers are stationary or move very little, allowing for the computer to render and use that many characters without noticeable slowdown.The graphics in the game are a little simplistic in most cases due to the use of a DirectX 9.0c engine. Effects like High Dynamic Range Rendering are noticeable, the terrain is liberally sprinkled with trees, grass, and the houses and roads look ok. To me, the main game could have been done on an Xbox 360 and in fact the Xbox 360 version of the game looks very similar to this game. That is, until you enable PhysX.

Sound in the game is rather uninteresting but the norm for a game with guns and people talking. Your character doesn’t speak but Dexter and Mother speak a lot. Voice acting is a subjective matter some will like it some will hate it. Gunfire for the most part sounds like gunfire with exploding shells and artillery for the most part sounding the part. PhysX, as you know is a NVIDIA owned technology that enables physics effects in games. Games like Batman: Arkham Asylum, Mirror’s Edge and others use PhysX to realistically show off fog, wind, leaves blowing and smoke. PhysX can also model destructible terrain and realistic cloth among other effects. The game without PhysX enabled is rather bare world with no leaves blowing little smoke on the battlefield. With PhysX enabled, the game is a totally different place.

The game uses NVIDIA PhysX in virtually every level to improve the environment and weapons. With PhysX on, there is ground fog in level that is realistic and reacts to soldiers moving through it. Ash in the game swirls around the environment in the Pompeii level. Leaves swirl around with wind are not present when the game has PhysX disabled. Smoke and dust is prevalent through the game with PhysX. Firing a gun causes smoke to come out of the gun. Firing a weapon in the game causes debris to come out of wood or stone. Some weapons have a totally different firing pattern than with PhysX off. PhysX allows you to totally change the look of the game you are playing and with Darkest of Days this shows. Performance with PhysX enabled on a ATI Radeon HD 5870 or HD 4890 was totally unplayable, as these cards do not support NVIDIA’s PhysX effects in their drivers but have to use the CPU to run the effects. Running the game on a NVIDIA GeForce GTX260, on the other hand is a totally different experience, with frame rates in the forties even with maximum resolution due to the PhysX running on the graphics card.