Extraordinary impact and visual conspicuousness.
Dr Slab is a super 3D serif family for posters, logos and all display. The basic idea is not a brand new. Stacking type system have been used since before wood type age. As you imagined, colored wood type(woodcut), many other engravings and contemporary printer machine print many colors separately with different printing plates for each colors.
Dr Slab uses the same system for 3d effect. Please use Photoshop or Illustrator, or your favorite graphic design apps that can handle layers. Layers are the printing plates of wood type. You should be able to change text color for each layers.
Dr Slab "Base" style is the core of this font family. You can add effects by using the other styles(Rim, Shadow, Ext).