This is a book cover design I did for a Kickstarter project for Rock Paper Books - read about here and watch the vid. I loved the idea and the roster of artists is insane. Some really cool interpretations. I always loved the movies 20,000 Leagues Under The Sea and Mysterious Island by Jules Verne. Mysterious Island always had this bizarre nonsensical quality to it, like there was sooooo much more to the story. 
I created the illustration on the iPad Pro using an Adobe Draw technique that mimicked old etchings and then did the type treatment and frame in Adobe Illustrator. 
It was interesting for me because i wasnt sure how I wanted to approach the illustration and I got to play in a few different styles before landing on this one. Tried to show a bit of it below. 
Alternate color approach. I was kinda torn because I liked the red and orange eruption feel but think the teal yellow look had more mystery. Easy to do in Illustrator once your file is all set up and organized. 
Close-up detail of the engraving technique. Not to push this into tutorial area but I used a small rounded end brush in Adobe Draw, and with the Apple Pencil was really able to control with pressure the thicks and thins. 
Early sketch done in Adobe Sketch, I obviously had some crazy ideas about how detailed I wanted it to be. I wasn't considering the scale of printing to well.
First approach involved a very dense level of detail and cross-hatch style. 
I got pretty far with another approach where linework was looser like I've used on several portraits lately. I liked it but it felt a little busy for the subject and when put up against the type I was working on it didn't seem to match. 
I also have really been enjoying using Adobe Sketch and the watercolor features so took some shots and a style that would be way looser with just some detail created with linework. I definitely want to revisit this style but still wasn't exactly what I was looking for.