Darby rendered with a bamboo pen dipped in Sumi ink.
Bamboo pens are one of my favorite traditional instruments for the completely unpredictable nature of how the ink is going to splatter and splash. It's an opportunity to become loose with your drawings and become less caught up on "perfection" and just, create something. Even had his face become splotched and splattered with black ink it could've made a really cool mask.
I wanted to draw Darby in a regal pose as though he was laying on one of those ancient Greek klines.

Done with sumi ink on paper