Fantastic Four Promo Poster- Herbe Trimpe & T. Smith

Herb Trimpe and Tom Smith nailed this back in the 90's

Per Tom this is what he calls a Blue Line painting:
Not a color guide. Just to clarify it.. It is a blue line painting here is the difference.. A color guide was just what it sounds like .. It was only a guide for the separators who took the color guide and translated into a hand cut or on computer for color separations or breakdowns of where color went on any given page. So the color guide never saw print because it was only a guide. Blue Lines on the other hand were fully painted works of color art that where scanned and just for the final image in the magazine / comic. In other words they were what you saw as the final product.