Good style, needs work.
I like the style and the timing of the humor. The end, however, seems a bit abrupt (the explosion looks like you just gave up). If you have the patience, try drawing out Nightmare yourself and having him interact with Goodfella Charlie. Sound was a bit tinny, and you could've done more with the picture of Pesci (add background, round the edges, add some text.
Overall, great concept, but a little bogged down in the production details. I'd love to see you give this another shot.