Research basically. The Mahabharata is a gigantic story told from multiple viewpoints and spanning generations. It's the longest epic poem ever written and is famously ten times the length of the Iliad and Odyssey combined. It doesn't really conform to the traditional 3-act structure of Hollywood storytelling and can be very difficult to grasp as a whole until after a few readings and some heavy background work on the philosophy of the Bhagavad Gita in particular. It's basically the story of every human passion told through the mythic images and events of the ultimate super-war and as such it touches just about every area of our common experience. You can't do a take on it without some maturity and experience of those passions — and if you haven't had a spiritual awakening of the kind Krishna provides for Arjuna you will struggle with and likely misrepresent the underlying concepts of karma and dharma which drive the whole epic.

Where did your interest in Indian mythology come from? Were you aware of them before you started working on this project?

My interest in Indian myths goes back to my childhood; I was obsessed with myths and legends of all kinds especially Celtic, Norse, and Indian myths which seemed closest to the science fiction and fantasy stories I liked to read. The Mahabharata, with its descriptions of gigantic armies of super-warriors, flying machines and what appear to be tactical nuclear weapons fascinated me and suggested the possibility that a more advanced civilization might have risen and fallen in the deep and distant past. As a kid I was a huge fan of the Beatles and when they got into meditation, sitars, and Indian culture I was inspired, years later as a teenager, to do the same. A lot of my work in comics - particularly in things like The Invisibles - has been inspired by Indian myth and philosophy.

In Invisibles, there's a strong element of moral ambiguity to the larger struggle, and the same is true in these stories. I've seen you point out that the good guys do "bad" things in these stories in order to win at times. It's something that's at once grander and grittier than a lot of modern myths; when you're working with this material now, are you surprised by the complexity of what's already there?

That's what I love most about the Mahabharata - there are no real heroes and villains. It's the story of duty - represented by the Pandava brothers - versus desire, as embodied by Duryodhana and the Kauravas. All of the heroes are forced to compromise and break their own codes of honour in order to win the fight and the villains are all given rich complex personalities which explain why they do what they do. Unlike, say, The Lord of the Rings where the Good vs Evil split is more obvious and Biblical, the Mahabharata presents a magnificent world at the end of an age of supermen and women - and shows the beginning of the dark age, in which we now live. This allows the story to present noble characters who can only succeed by adopting all the flaws of the fallen humans who will be their successors. It's a far more honest and contemporary take on realpolitik than we find in most epic stories or fantasy tales and you can see in Mahabharata the source of the moral ambiguity and complex interpersonal dynamics of something like Game of Thrones.

This project has been in the works for a long time, with the first comic book version announced back in 2010, and that itself coming out of an earlier animated project. Has your concept of the story you're telling (or how to tell it) changed during that time? Are there elements that you wish you could go back to tweak, or have you done so, for that matter?

Well, 18 Days was originally intended as an animated web series so I prepared a massive bible document with artist Mukesh Singh and pretty much nailed down how we wanted this new version to look and feel. I did an exhaustive amount of research for this project and the story was already there for me, so all I really had to do was find a modern tone and voice and figure out a way to organize the material that changed the structure but kept what I felt was important to this somewhat stripped back and streamlined take on the material. Which is to say, there's not a lot I would change - unlike a lot of my work, which is done in a more improvised, free-form way, the planning for 18 Days was fairly meticulous.

Even though you talk about working in an improvised manner, you're famous for your notebooks and preparatory work. As the 18 Days: The Illustrated Scriptbook that's making its digital debut in this Humble Bundle shows, there really is an astonishing amount of planning that's gone into this series. Is this just a natural form of working for you, even if all the material you come up with doesn't work its way into the eventual finished product?

It's the only way I can work. I have teetering mountains of these notebooks now - I get through one every couple of months and on a big project sometimes one every week or so, going back 30 years! I generally start with sketches and drawings to warm up. I like to see the characters before I start shuffling them around.

The first installment of 18 Days, Avatarex Chapter 1, is getting its exclusive debut through Humble Bundle. [Artist Jeevan J. Kang is drawing the series.] With things like Thrillbent, Monkeybrain and other digital-first release models coming about for comics — and obviously, Netflix and Amazon and others doing similar things for television and movies — is the way in which technology has changed the availability of material something you find yourself thinking about? Do you want to do more digital work?

I'm in Los Angeles right now with an internet connection, but back home in rural Scotland where I work I can't get a signal so generally I have no internet, no phone, and no watch. My wife, Kristan takes care of everything involving communication! Which is to say, I rarely think about how my work is being read so I'm rubbish at answering questions like this! [Laughs] I do like the democracy of digital comics - they can be sourced and read anywhere, anytime, and that aspect of it is something I'd like to get into a little more. Short answer, yes. I want to create work for all available delivery platforms.

You've had a strong year in terms of breadth of material released, with DC's Multiversity, Image Comics' Nameless, Annihilator for Legendary, the newly announced Heavy Metal editor-in-chief position and now this. What's next? "A rest" is a perfectly understandable answer.

I'm like a shark; if I rest I die! Next up in comics is a Santa Claus origin story I'm doing with artist Dan Mora for Boom! Studios, then there's the long-awaited Wonder Woman: Earth One graphic novel that Yanick Paquette has just finished drawing — that's out in November. Otherwise, I've been doing a lot of work outside the comics business for a while. Since I came off the grind of the monthly books at DC I've been enjoying stretching my wings and taking the opportunity to try my hand at more diverse stories and projects.

The Humble Bundle Presents Tales From India ft. Grant Morrison and Stan Lee bundle will be available until 11am Pacific July 23, with Morrison's Avatarex and 18 Days: The Illustrated Scriptbook available at the $15 and above level. The charities benefiting from the bundle will be UNICEF and Worldreader. More details can be found at the official Humble Bundle site.