Reading this wonderful article titled Pixels and Voxels by Matej Jan. Even if you already know what's up, there's an incredible expose of artwork from both visual styles that's worth scanning. https://medium.com/retronator-magazine/pixels-and-voxels-the-long-answer-5889ecc18190#.bacbye8p2
Matej is the enterprising lad behind the unique Pixel Art Academy game that teaches you how to draw pixel art.
Zelda 3D isometric by Sir Cama.
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