CM Punk is a former WWE Champion and one of the most popular pro wrestling stars in recent history -- but he's moved on from that career to focus on his new goal of mixed martial arts. Oh, and getting Galactus drunk.

A passionate comic book fan, Punk makes his debut as a comic book writer with this week's "Thor Annual" #1, on sale today. Punk teamed with fellow Marvel newbie Rob Guillory -- artist of fan-favorite Image Comics series "Chew" -- for a 10-page story featuring young, pre-Mjolnir, Thor taking on Mephisto (basically Marvel's version of Satan) in a drinking contest.

CM Punk on "Thor Annual," Potential Future Comics Work

Neither Punk or Guillory plan on making the "Thor Annual" -- which also includes contributions by series writer Jason Aaron, "Lumberjanes" co-writer Noelle Stevenson and artists Timothy Truman and Marguerite Sauvage -- their last work for Marvel, and discussed both this story and future plans in an interview with CBR News. And while Punk has chosen many uniquely physical paths in his career, he disclosed the relatively sedate world of comic book writing is "more nerve-racking than getting punched in the face."

CBR News: Punk, Rob, past interviews have indicated that the two of you were friendly with each other before starting work on the "Thor Annual" story. In what ways do you see that existing familiarity reflected in the final product?

CM Punk: I think just being buds already sped up the "getting to know you process." There was no introduction needed, so we went right to trying to think of a way to get Galactus drunk. We will succeed one of these days.

Rob Guillory: Well, we'd already established that we had similar interests and a similar sense of humor, which really helped us mesh in the work, I think. There wasn't a getting to know each other phase to work past. From Day 1, we were e-mailing each other like, "Can you believe Marvel's gonna pay us for this?!" and giggling like schoolgirls. Very professional.

A young, reckless Thor engaging in a drinking contest seems pretty far removed from a disciplined athlete famous for a straight-edge lifestyle. Punk, how did you get into young Thor's head for this story? Was it a pretty natural character to connect with?

Punk: People told me to write about what I know. Of course, there's been a chorus of comments about me being straight edge. I'm not sure why it's so surprising, I've been surrounded by people who drink my entire life. The sober guy always has the truest accounts of what happened the night before! The Thor who thinks he's worthy but isn't was easy to tackle.

CM Punk Makes his Marvel Writing Debut on "Thor Annual" #1

Between making your comic book writing debut and training for your first UFC fight, you're looking at a lot of major firsts in 2015. How satisfying is it to be exploring so much new territory right now in your career -- and are there more worlds left you'd like to conquer?

Punk: I'm free for the first time to capitalize on all things that come my way. It's exciting and refreshing. I enjoy doing new things, no matter how difficult. To tell you the truth, writing a comic book is more nerve-racking than getting punched in the face.

I'm waiting on Marvel to cast me in one of the upcoming awesome movies they got coming out! Always new worlds to conquer!

Rob, you've been mainly focused on "Chew" for the past several years. How much did you enjoy getting to move to a different type of setting for the "Thor Annual" -- along with the chance to draw multiple iconic Marvel characters?

Guillory: It was a nice break from the usual "Chew" work, after six years and 47 issues of being totally engulfed in the world of Tony Chu. So it was really fun to stretch my legs with a totally different set of characters. Plus, I've been a Marvel fan since I was a kid, so getting to play with characters that I grew up with was a dream gig. And it was made even sweeter by the amount of creative freedom Marvel was willing to give us.

From the interior pages that have been seen to the variant cover you illustrated, it looks like you had a lot of fun with this story. Given how serious mainstream superhero comics can often be, how pleased were you to work on something comparatively lighter? And how much freedom were you both given to really embrace the craziness?

Guillory: Yeah, I had a blast working on this. And honestly, as a creator who primarily does weird non-Big 2 work, I was sorta waiting for my Marvel editors to crack the whip at some point and say "Hey, you can't draw Hulk with a Luchador Mask. That's too crazy." But that never happened. Literally, every crazy, silly idea I contributed was met with the editors saying "That sounds hilarious. Do that." I was able to draw the crazy Marvel comic I wanted to, and I'm still in disbelief a bit. I sorta feel like I got away with murder.

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Punk, you've made it clear that, for as much as your schedule allows, you'd like to continue writing comics. How much thought have you given to what you want to do in your next story? And as a first-time comics writer, how much did the experience live up to -- or defy -- the expectations you had going in?

Punk: I'm still gong to write Punisher. Some day. I figure once I get some more jobs under my belt the experience will help me formulate a much longer story. I've talked with Marvel about what's next and it's going to be great!

Writing a comic for the first time was a little harder than I thought. I expected it to just come out when inspiration hit me but I really had to lock myself in a room and focus. Once I did that, it was cake.

"Chew" of course keeps you busy, Rob, but are you hoping to do more at Marvel down the road? Or are you planning on primarily sticking with the creator-owned realm?

Guillory: Well, "Chew" is winding down fast, so that's a factor. We'll be wrapping it at issue #60 in a little over a year, so after that, I'm absolutely planning to pitch some Marvel stuff. And even in the meantime before "Chew" ends, I'm open to occasional Marvel cameos.

"Chew" is my absolute priority right now, and I absolutely plan to do more creator-owned stuff post-"Chew," but yeah, I'd love to play with more Marvel characters down the road. I'm a Marvel kid at heart.

"Thor Annual" #1 is on sale now. [CBR Senior Editor Stephen Gerding contributed to this report.]