Hex color seems washed out in cycles

[MarioPeper]

a path tracer like cycles is unsuitable for something like that, so you better take the workbech

How to lit a scene without lights of any type, nor shadows. For a cartoon look?

I haven’t looked at the tutorial, but with this simple workbench render setup you have shadeless textures. [flatshading] For layer painting fun in 2.8+ I recommend this addon: https://bitbucket.org/mephisto_/blender_paint_layers/downloads/