I'm no artist, but here is my attempt to describe it:
- Realistic (not cartoony, cell-shaded)
- 3D (not 2D)
- Science fiction (robot)
- Industrial (no plants and wildlife)
- Dark (plenty of shadows)
- Present (not futuristic)
- Limited presence of fantastical elements (fantastical elements are things like magic and such)
- Technology (not space-magic etc.)
I'm not sure if you played the game or not, but it should matter anyway.
What do you think about these textures though? Don't they seem like they have this cartoon like touch/colors to it as Valve used in Team Fortress 2? Not the models, the models are definitely realistic, but the textures.