original illustration 10-15 Minute sketches June 10, 2018 / As the title says, a number of quick (10-15 minute) sketches. I love making these! 10 minute sketch. No references. 10 minute sketch. No references. 10 minute sketch. No references. 15 minute sketch. No references, and playing with colors. 15 minute sketch. No references, and playing with colors.