Duke Nukem 3D--godfather of the first-person shooter--has been revamped and re-released nearly a dozen times over the past 20 years. It's appeared on devices ranging from the ubiquitous iPad to the ill-fated Sega Saturn. But according to Gearbox Software publishing producer Scott Warr, nothing beats the 1996 original.

That's why his team--which includes several members of the original development team--has assembled Duke Nukem 3D: 20th Anniversary Edition World Tour, a definitive update that both preserves the original experience by implementing only a crucial handful of visual improvements and delivers eight brand new levels that aim to recapture the series' early glory.

We sat down with Warr during PAX West to discuss what's changed (and what hasn't)--from multiplayer to voiceovers to classic expansions that didn't make the cut.

GameSpot: Let's start with the eight new levels. Are they all about equal in length to the original levels?

Warr: Yes, absolutely. That was what we got when working with [original developers Richard Gray and Allen Blum III] again. They went through the same type of things that they did in the original Duke Nukem 3D. As you play through, you should notice no difference. It feels just like a continuation of Duke 3D. You'll play the fifth episode and be like, "When did this come out?" It doesn't feel like it was just created in now. There are some definite things that you'll see with the lighting that we could not do back in 1996 that we can do now. Other than that, you shouldn't feel anything jarring or different.

Why remain so committed to those retro stylings rather than updating the experience with modern techniques?

Duke Nukem 3D turns 20 this year. It was really important for us to keep Duke Nukem 3D in that retro feel and look. [However] it's not an up-res. We didn't do the new true 3D renderer. As you can see when you look up, things aren't stretched anymore. It actually stays and looks like buildings or whatever. The skybox looks like a skybox. We also relit the entire thing.

You can flip between the new renderer and old renderer. It was very painful, especially from the tech end of it, [but] we did not want to touch the game. Because of the anniversary edition, it was discussed at some point, like, what does the anniversary mean? It was definitely to just keep Duke as original as possible with a few tweaks.

So even the new levels don't have new mechanics of any kind? It's the same classic weapons, same jetpack, same steroids…

I will say we did add some things that were kind of within code but never really hooked up. There was a flamethrower-type weapon that was in actual code, but it was never in the game to actually use. We hooked it up, and it's called the Incinerator now. We also added one new enemy type, which is the Firefly. They look tiny, like they got shrunk, and then they'll expand into big monsters and shoot you with flames.

Can you tell us more about what you guys changed visually and how you went about building the new levels in the classic style?

We kept it all using the original tools [and] original assets. Everything in this new level is actually from the original game. We just used it in different ways, shapes, and forms. With the technology where it's at today, we could do some new things, new tricks, and didn't have to stay with just within the confines of the old renderer.

Did you update the audio at all? All of Duke's lines have been re-recorded by original voice actor Jon St. John, correct?

Correct. The old files were pretty harsh, so just we called Jon St. John. He was like, "Of course." He did all the lines over again and, actually, recorded some new lines just for the new episodes. You will hear new things from him. Then [original composer] Lee Jackson added new music and is the composer for the new levels.

How difficult was it to convince all these original team members to get involved? Who even made those phone calls?

[Gearbox Software studio head] Randy Pitchford with the 20th anniversary was like, "Hey, we've got to do something." Called [Blum] and [Gray], and they were like, "Let's do this." It was great. I remember some of the earlier emails. They had already gone through and said, "Okay, we want to do this world tour thing. We want to go to different locations around the world."

As far as jumping in and using all the tools, I remember some of the complaints of like, "Ah, crap. Now I remember this," or, "Oh, I forgot the trick that I was supposed to do to make this work." That was awesome to watch because me being a fan, I was sitting there like, "I can't believe this is happening."

Some of it's captured in the developer commentary as well. You can hear some of what they were frustrated about, but it was pretty easy. [Jackson] was stoked to write new music for the fifth episode. Like I said, both [Blum] and [Gray] were onboard. Jon St. John, he's always ready to do the Duke Nukem voice.

You mentioned the "world tour" aspect of the new levels--the one new level we've seen so far is set in Amsterdam. Why did you pick Amsterdam of all places? And what can you tell us about the remaining levels?

It was just one of the locations around the world that we wanted to visit, or that had an alien problem. A lot of the [original] assets were just reused in different ways or little twist on them, but it was mainly the old assets. Other than that, it's just around the world. There are eight different locations. It ranges from Amsterdam to Russia to San Francisco--there are cool locations all over the world, and you will recognize some of them.

Can we expect any new boss characters?

I will say that there is a boss at the end of the eighth episode that you will fight.

What about multiplayer? How are you handling that?

We rewrote multiplayer from the ground up. Eight-player multiplayer, eight-player co-op, and now we have one-player bot matches. It'll be one player and then seven bots. That's never been done before, or hasn't been in Duke Nukem 3D. It was there, it just wasn't hooked up, so we hooked it up and made it available. Basic DukeMatch is back and you can play it or even go through the eight new missions that we added.

What about some of the expansions that have come out over the years? I know a lot of fans were sort of clamoring for material like Duke It Out In D.C. and other classic add-on content that they were hoping might be included in this package as well.

Correct, and it's not. You know, we liked the new maps that had come out over the years, but as of right now, there are no plans. Those were not included just because I think we wanted to keep it with [Blum] and [Gray]. It was to focus on the original 20th anniversary. It was to get the original game and then these new episodes.

Now that the eight new levels and the classic game are shipping next month, would you consider adding any of that older add-on content at some point in the future?

It's not out of the question. While I'm at Gearbox Software and we have Duke Nukem on the plate, anything's possible. I love Duke Nukem. I've been a fan ever since the first game. It will always have a great place in my heart. I never want it to go away.

Duke 3D has been re-released quite a few times over the years, most notably as the Megaton Edition that was previously available on Good Old Games. A lot of people bought and played that game. To the fans who already own versions of Duke 3D, what would you say to convince them to buy Duke again?

You know, some of the things that we noticed from Megaton and then from the Xbox 360 version--we basically just combined them all and put it [in Duke Nukem 3D: 20th Anniversary Edition World Tour]. I know on the Megaton version, the rewind feature was not there. It is going to be on the PC version now. We wanted both versions to just be in one spot. We did a little bit more, but we definitely took the components of the 360 version and Megaton and put [them] into one spot.

Duke Nukem 3D: 20th Anniversary Edition World Tour releases October 11 for PS4, Xbox One, and PC at $20. For more on the original announcement, check here.