Some more sketches for fun!

Just thought i'd take this time to show off some more sketches that I have done up lately ranging from 10-20mins up to an hour or so i'm guessing usually never check the time when im drawing so haha. First off gonna show of a quick Frankenstein sketch that I did on a envelope it was about 20mins or so nothing to amazing pretty quick piece.

Next piece is just some random superhero quick sketches that I did up one night for fun. Turned out pretty decent I think for being pretty quick gonna guess around 40mins to an hour tops.