Opacity in pixel art?

hey, @willt said that many people uses opacity while drawing on pixel art, i would like to see some examples about this
probably it will be useful for other persons too, i have never used or seen someone use opacity in pixel art before

It depends on the specific pixel art style. If you want to do “classic pixel art” which uses a limited set of colors, you shouldn’t use opacity or blending modes, but then there are other styles, like the one from Octavi Navarro:

http://pixelshuh.com/

Which I guess that he uses a lot of blending modes/opacity/effects.