These are some Tribes-inspired levels designed with the help of procedural terrain generation programs World Machine, Geoglyph and World Creator. I modeled the structures in Maya or Sketchup. The terrain textures I purchased from CGTextures and Gametextures and the skies are from UDK.
I had trouble finding trees with the right low poly stylized look I was going for, so I purchased the only one I liked, smoothed it out a bit and then broke it into pieces and reassembled them in Blender to create a variety of trees with the same style.
I set up all of the environment and sky materials on this page in Unreal. They’re not as good as what an artist would come up with but they look nice enough as a starting point. For the level below I purchased a clump of three palm trees, separated them to allow a wider variety of placement options and cleaned up their overlapping leaves.