After introducing the teenage superhero Boy Thunder in an early story arc of Batman/Superman: World's Finest and revealing him to be the eventual antihero Magog from the seminal story Kingdom Come, Mark Waid and Dan Mora are returning to the world of Kingdom Come in the latest World's Finest storyline. Starting in Issue #20, Batman and Superman will explore Earth-22, the alternate universe where Kingdom Come takes place, to learn what happened to Boy Thunder after Superman's estranged former sidekick was whisked back to his native dimension. The superhero duo will find themselves facing their Earth-22 counterparts as the Kingdom Come Superman and Batman deal with what has become of their world.

In an exclusive interview with CBR, Mark Waid revealed why now is the perfect time to tell the origins of Magog and revisit the Kingdom Come world, teased how the World's Finest story will unveil parts of Kingdom Come never before seen, and hinted at what fans can expect as the story kicks off this October. Waid and DC also shared exclusive unlettered preview artwork from Batman/Superman: World's Finest #20, illustrated by Dan Mora and colored by Tamra Bonvillain.

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Batman/Superman: World's Finest #20 Cover

CBR: Boy Thunder showed up in an earlier arc of World's Finest and was revealed to be Magog. You've mentioned you've had this origin for Magog for a long time. What appealed to you about revisiting that idea in World's Finest?

Mark Waid: It was the itch to tell that story. It's one of the few Superman stories that had never been told -- the idea that Superman had a sidekick for some length of time. There were some stories where he had a sidekick for nine pages, but I wanted to do something that was really diving into how Superman would deal with a younger character if he was in a Batman role.

Superman didn't have Superboy yet when he first met Boy Thunder. What did you want to accentuate with him regarding that then and now in this new story arc starting in World's Finest #20?

Because Superman will take responsibility for something, whether it's his fault or not, he's going to want to take responsibility for the idea that Boy Thunder has grown up to be somebody who is not following the Superman code. Did he teach him enough? Did he teach him the wrong things? Was he a good enough role model?

The preview art reveals Superman and Batman visiting the Kingdom Come Universe, including parts we've never seen before. What elements of this universe did you really want to dig into that you didn't explore in Kingdom Come or The Kingdom?

There's a ton because this isn't so much a sequel as it is a prequel. We do flash-forward a few pages into post-Kingdom Come, just to set up the world, but most of this is taking place in the before-times in an area of time somewhere between the World's Finest era and now in the DC Universe.

This gives us a chance to explore all those characters in the Kingdom Come Universe, how they're different from our characters, and [how they] became the Kingdom Come versions that we know. We get to touch on a lot of characters that we didn't get to see in Kingdom Come, which seems impossible because there are 8000 characters in Kingdom Come. But we touched very little on the villains and supporting characters, and there's a lot of room to play there.

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Batman/Superman: World's Finest Flash runs in

If Kingdom Come was a commentary on '90s antiheroes, how did you want this story to speak to the superhero genre of today?

There's a tendency among fans and some pros to very rigidly classify the eras of comics -- the Golden Age, the Silver Age, the Bronze Age. To me, it's all one big, flowing history. Just because something took place in a comic in 1962 doesn't mean you can't revisit it in [the] modern day with a modern point-of-view.

This whole thing is about finding ways to blend Golden/Silver/Bronze Age concepts with a modern form of storytelling so that it doesn't feel cheesy or outdated, and it's also to show proof that there is a lot of life left in those comics.

You followed up Kingdom Come with The Kingdom. How did you want to reinterpret some of those themes and story beats with this story in World's Finest?

We will learn the definitive origin of Gog, and it may or may not line with The Kingdom, but it certainly lines up with Kingdom Come.

Dan Mora is back with this story arc. You've still been working with him on Shazam!, but how was it working with him to revisit the world of Kingdom Come?

It's amazing! If anybody can hold a candle to Alex Ross and Alex Ross' designs in particular, it's Dan. Dan has a way of interpreting even the most classic characters in a very modern way of envisioning even the simplest and most iconic costumes with a style that makes them look very contemporary.

You've mentioned that you checked in with Alex Ross and updated him on what you're doing with this story arc. When telling a Kingdom Come story without him being in the room, what do you try to be mindful of as you build upon this foundation that you and Alex laid down all those years ago?

The first thing to be mindful of is to not undermine that in any way [and] to try to work within that continuity. We talk all the time about this, and I wouldn't have approached this story at all if it had been a direct sequel to Kingdom Come with those characters. I've already done The Kingdom, and to do it without Alex at this point would seem futile and foolish. Setting it as a prequel, among other things, gives me a chance to carry forth a lot of the ideas that Alex and I talked about that didn't get into the series originally.

It also gives me a chance to pick Alex's brain about the way he envisions Gog and that character that didn't come across on the page, not only in The Kingdom or Kingdom Come but also in the Justice Society stuff that he did with Geoff Johns. There are still a lot of pieces of that mythology behind Gog that are strongly [rooted] in Alex's ideas and that we get a chance to communicate.

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Batman/Superman: World's Finest Earth-22

The last time we saw Boy Thunder, he was not in a good place. Where is David's mind at the start of this story arc?

He's a few years older because time is passing a little bit differently on the Kingdom Come world than it is on our world. He's immediately recognizable to Superman, but he's become Thunder Man. He's grown to his late teens or early 20s and has some misgivings about how much time has passed.

For Superman and Batman, it's only been a few weeks, or maybe a couple of months, since they last saw Boy Thunder. To Boy Thunder, it has been years, and he cannot help but feel a little acrimony about the fact that Superman promised to find him, and it took him this long.

We see the Batman and Superman of Kingdom Come together at a funeral. At the start of Kingdom Come, they were very much at odds. What's their dynamic like in this story?

It's very much like it was in the epilogue to Kingdom Come that took place on Planet Krypton. They've laid down their swords, and they're best friends once again. This sequence would take place either right before or right after that.

World's Finest has always been a book with Superman and Batman teaming up with other DC characters, but now you're juxtaposing them with the Kingdom Come Superman and Batman. How did you want to compare and contrast these different versions of the characters?

The fun thing was realizing that I could tell the story focused on our world's World's Finest team, but I could also take parts of that story and focus them on the Kingdom Come Superman and Batman as a team, writing that book in places where they're the stars and our Superman and Batman are guest stars. It's not just using the Kingdom Come characters as guest stars but really making them the stars of World's Finest for an issue or two.

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Batman/Superman: World's Finest Kingdom Come funeral

I love the recent issue of World's Finest: Teen Titans, with the Titans attending a Titan convention. What appealed to you about crafting a self-aware story for the Titans dealing with their fans?

It was a blast. Ema Lupacchino, God bless her, drew an entire convention hall full of people on every page. I don't know how she accomplished that. I felt so bad. I'd ask for things like "Panel 1: There's a stage full of people and a whole crowd listening to a panel. Panel 2: More of this."

It plays into one of the overall themes of the series, which is, "How public do you want to be as a superhero?" As Batman keeps warning them, what does it mean to be an Instagram superhero? What are the downsides to that?

A recurring element in your recent DC work is a focus on younger heroes, like Shazam and the Teen Titans. What is it about focusing on a younger generation of heroes?

It gives you more places to go. It gives you a place in the DC Universe where you're off in your little corner, and you can develop continuity that will play into the main continuity of the DC Universe without having to worry about the fact that they're characters appearing in six other books right now. The fact that they're young is more of a coincidence than anything else. It's just stories from back in the day.

Boy Thunder started out as a wish-fulfillment character, getting to be Superman's sidekick. Is a recurring theme in this coming arc about the cost of that dream going horribly wrong?

Yes! Another theme of the upcoming story arc is [that] because our World's Finest team has gotten a glimpse into the post-Kingdom Come world and the devastation, they know Kingdom Come is coming. They can't tell anyone off Earth-22 about the future, but at the same time, our Superman can't help but look at that Superman, not knowing all the events that led up to Kingdom Come, as a failure.

He looks at that Superman as someone, from our Superman's point-of-view, who clearly was not capable or interested in protecting his friends and colleagues. To let something like that happen is unthinkable for our Superman. Of course, we know better. We know that there are real reasons for that, and that's something our Superman is going to have to learn.

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Batman/Superman: World's Finest visit Kingdom Come

Since we're talking wish-fulfillment characters, you're also working on Shazam!, who personifies that.

He's the ultimate wish-fulfillment character. The appeal of that character is that you don't have to be a billionaire or come from another planet. All you have to do is say a magic word, and suddenly, you're a superhero. There's nobody in the world who can't connect with that in some way.

In Shazam!, we're seeing the pantheon of gods that give Billy Batson his powers coming after him. Where did the idea to lead off the series with this story come from?

That was largely Patton Oswalt's cue. We were at a party early on as I was working on Issue #1, and he asked me, "If he's got the power of Zeus, why isn't he as horny as Zeus?" That opened up the entire thing for me, so I could've given Patton a big, wet kiss [at] that moment for opening up that entire arc for me.

That's where that came from, the idea that gods are egotistical, gods are very self-centered, and [the] gods you are representing want you to represent them in the truest form possible.

Mark, what can you tease about Batman/Superman: World's Finest as we get into Issue #20?

There are lasting consequences to our Superman and Batman's visit to Earth-22. There may or may not still be a future for Boy Thunder. Whether or not he becomes Magog in this story is a question you'll have to find out as you read.

Batman/Superman: World's Finest #20 goes on sale Oct. 17 from DC Comics. The issue is written by Mark Waid, illustrated by Dan Mora, colored by Tamra Bonvillain, and lettered by Steve Wands.