Step 15: Darken the lines on the top, left side of the head for this Nintendo character's first horn. Draw a couple of curved lines under the horn for the thick base. Darken the curved lines to the right of the head to create Bowser's other horn. Draw a couple of shorter lines under the horn for the base but don't overlap the hair. Draw a couple of slit-like shapes inside the muzzle for the nostrils.
Step 16: Darken the left edge of the small circle on the left for the fist. Make the line more wavy for this Super Mario Bros. character's knuckles. Lightly sketch a series of curved lines across the circle for the folded fingers that form a fist. The fingers look similar to the number 3 with an extra line at the bottom. Darken the lines when you get them right. Draw a curved line along the top, right edge of the initial circle for the thumb that's folded over the fingers. On the bottom of Bowser's thumb, draw a small line for his claw.
Step 17: Draw a rectangular shape across the arm guide for the studded band. Bowser's arm band should be very close to the fist. Sketch lightly at first and then darken the line when you get the shape right. Draw a series of small, triangular shapes across the band for the pointy studs. Darken the initial arc-like guide for the arm but make the line more wavy for the muscles. To the left of the fist, draw a curved line for the studded wristband. Draw a few small, triangular shapes along the wristband for the pointy studs.
Step 18: Draw a couple of small cone shapes along the curve on the back for the spikes on the shell. Draw the cones close to the edge of the initial oval. Add a curved line under them for the spike's base. Draw the first two spikes far enough apart so that there's plenty of space between them. Draw a couple more spikes in the space remaining but don't add the curved base at the bottom. Darken the initial oval for the top of the shell. Draw a couple of curved lines above Bowser's arm for the lower edge of the shell.
Step 19: Draw a few small, triangular shapes along the left side of the jaw for the studs on the collar. Draw a curved line that connects the studs to create the actual collar. Darken the initial oval to create the body. Make the bottom edge lower than the initial oval. Draw a long, curved line across the front part of Bowser's body for the edge of the chest plate. Draw a series of curved, horizontal lines for the ridges on the chest plate.