So back in the misty days of your that was 2012, @Human/Kreuzer was doing the King of Pocket full game. At the time, they were using NGPC sprites re-shaded in a particular style, and they had a tutorial up on their (now dead) website to illustrate how this re-shading was done.

Does anyone have a copy of that tutorial? I'm thinking of using a similar style for a future project, only with the website defunct I can't seem to get hold of it anywhere.