I worked solo on my project, but the main technical contribution I did to the base project was Depth of Field - the aperture size in the image is 0.03, with the zFocal plane set at 2.2f (the entire scene is SUPER small). The complex models, like Companion Cubes, Chell, the Button, GLaDOS, and the numerous turrets were downloaded from online; the Level 50 'poster' at the left hand side of the image is an image slapped onto a rectangular prism. The floor itself is a plane with another tile texture on it. Lighting in the image consists of 3 point lights; one to the lower left of Chell, to the lower forward direction of Chell, and to the lower right of Chell (they're all very close to the ground).
My inspiration for my image came from my love of Portal - I thought something surreal and dark would adequately depict the battle between GLaDOS and Chell. The 'glass' Companion Cubes looked cooler than just the normal textures, so I left them as 'glass.' I left no background because the black void seemed to heighten the drama of the scene.