Pixel Logic - A Guide to Pixel Art
https://www.youtube.com/watch?v=YkNmiIbAp9g
Ch.0 - Introduction
Ch.1 - Line art
Ch.2 - Anti-aliasing
Ch.3 - Colours
Ch.4 - Readability
Ch.5 - Dithering
Ch.6 - Game perspectives
Ch.7 - Clean-up
Ch.8 - Subpixeling
Ch.9 - Animation