In “a sketch a day” plan, I felt like drawing TFA Prowl and birds,since A.) I love both of them and B.) Prowl does love animals and nature in canon. So I used a 0.4 pen for the lines and shading. I had to use some research in some birds though. A shame that I’m not familiar of drawing birds of different kinds despite how I like them. I thought of using the brush pen for thicker lines, but ultimately I decided this is enough.