World Machine - Command powerful tools like erosion and advanced colormaps to create terrain heightmaps, meshes, and textures for your game or 3D scene. Download for Free!
Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
Vue - Create vast expanses of terrains, add trees, select the best point of view and render...
Pixel Studio - The Pixel Art Is Always Fun
Hexagon - Hexagon - Box Version
Piskel - Piskel is a website where designers online create sprites or pixel art.