Urban Sky Horizon Textures Theses are textures created by VALVe that are used to better blend the fog in your 3D skybox with the 2D skybox. They are optional to use, but provide a really nice effect in your level. 1.0 Version 3873 Downloads 55 KB File Size December 2, 2017 Last Updated MD5: 9f92ea432398913fc268e62c78634ccb Download