Skybox For Game Needed

I need a standard skybox consisting of 6 square textures which can be put on a six sided 3D cube that surrounds the camera in a game engine and thus simulates the sky. The skybox should contain clouds, stars and a fullmoon together with a slight halo around the moon. I include a sample of a skydome texture that represents the general setting I need, just that the sample has no stars and is for a skydome rather than for a skybox The general mood of the skybox textures must be suited for a horror scenario, so not too colorfull, not too blueish or poetic. The stars may be clearly visible, even a milkyway may be hinted, however, the sky should avoid an elvish - beautiful look and stick more to the black and grey look with only some color. The skybox needs some terrainfeatures in order to mark the horizon. It should come in two versions with different markings: A) with terrain features such as hills, mountains trees and so on, suitable for a gamelavel in the wilderness. the moon should be under 45 degree height so that it appears closer to the horizon in this scenario B) with cityscapes surrounding the horizon. the houses should be visible as dark silluetes, perhaps with lit windows, but can show some details, however they must not be lit too well. The moon should be high in the sky so that it is visible while the camera is in a city. If you have played "Vampire Bloodlines", that is a good example of what I need. The houses should not be hypermodern, rather neutral in style. Each of the skybox textures should be delivered in photoshop psd file or another lossless compression with a resolution of 2048*2048 in 32 BPP color