This Inktober prompt is "Tree". I took a shot at imitating sumi-e with various shades of grey marker. The result was serviceable, but you lose the ability to effectively mesh practiced stroke and end result. For example, the you lose the ability to plan and use the natural drying of the ink on the brush to create lighter areas. With marker, you have to jury-rig a similar look. That said, not bad for a first attempt.