didn't expected to came out with an entire monster lineup today during the downtimes at work.
again, 
Nate Wragg's style simplicity and effectiveness keeps inspiring me lots.
i like the idea to reproduce the feeling of a real drawing in photoshop, so here it is my small guide to how i manage to do it!
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| here is the plain drawing. just a black rough sketch with a color above it. |  | 
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| selecting "drop shadow" from the fx panel... | 
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| ... i add a small sharp shadow to make the blue spot look like a paper cut. | 
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| with FILTER>BRUSH STROKE>SPATTER i add some randomness to linework and edges. (you have to flatten the image to make this effect work properly) | 
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| with FILTER>ARTISTIC>ROUGH PASTELS i add some paper texture and pastel melting (again, the image need to be flatten to make it work as above) | 
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| finally i add one of my fav paper textures in normal mode around 20%. and here it is, done! =) | 
here and 
here a link to my texture paper. hope you enjoy and find useful this small tutorial!