Interview
September 9, 2025
Built with UE5, Borderlands 4 delivers ambitious scale with World Partition, Nanite, Lumen, and more
Gearbox Software is an award-winning developer of interactive entertainment based near Dallas, Texas. Founded in February 1999 by game industry veterans and led to this day by its founding developers, Gearbox Software has distinguished itself as one of the most respected and recognized video game makers in the world.
It’s been over fifteen years since the original Borderlands made its debut and, since then, the franchise has become one of the most iconic in gaming. When setting out to develop the latest installment, Borderlands 4, developer Gearbox Software’s aim was to deliver the biggest, most badass version of the looter-shooter series to date with an all-new emphasis on player freedom.
To accomplish this, the team used Unreal Engine 5 and leaned into features like World Partition to achieve the game’s ambitious scale while implementing innovative new mechanics for environmental traversal and enhancing immersion with dynamic time of day and weather.
Now, with Borderlands 4 set to take the industry by storm, we caught up with Gearbox’s Technical Director, Neil Johnson to learn more about the team’s use of Unreal Engine 5 to go bigger and better than ever before—and deliver the best, most beautiful Borderlands yet.
To accomplish this, the team used Unreal Engine 5 and leaned into features like World Partition to achieve the game’s ambitious scale while implementing innovative new mechanics for environmental traversal and enhancing immersion with dynamic time of day and weather.
Now, with Borderlands 4 set to take the industry by storm, we caught up with Gearbox’s Technical Director, Neil Johnson to learn more about the team’s use of Unreal Engine 5 to go bigger and better than ever before—and deliver the best, most beautiful Borderlands yet.
Thanks for joining us, Neil! So, what are your core goals for this latest installment in the beloved Borderlands franchise?
Neil Johnson, Technical Director: Our core goal, above all, is to make the best Borderlands game yet, and I think we’ve done that. Of course, it’s our customers who will tell us whether we’ve achieved that.
In concrete terms, we want to provide a game that gives the player more freedom than they've ever had in a Borderlands title: more freedom of movement; freedom to explore a larger world; freedom even from loading screens (as much as possible). We want our long-term fans to feel that this installment is faithful to the franchise, with more of everything that they love: more loot, more depth, more ways to be a badass vault hunter. We want them to live in this world for a while and have fun there.
Image courtesy of Gearbox Software, 2K Games
Borderlands 4 offers more expansive environments and opportunities for exploration than ever before. How has Unreal Engine 5 helped you achieve the sheer scale of Kairos?
Johnson: This game would not have been possible without Unreal Engine 5's World Partition feature. In past titles, we've had to do a lot of streaming management ourselves and were always limited in what we could do. World Partition makes level streaming so much easier. World Partition gives us the ability to present a larger world to the player than we would have been able to do otherwise by ourselves.
Similarly, One File Per Actor made it possible for more designers and artists to work in maps at the same time without stepping on each other’s toes. Although the transition to this new system came with some difficulty early on, I can’t imagine going back to the days of one dev at a time making changes to a level.
Image courtesy of Gearbox Software, 2K Games
The Borderlands series has one of the most passionate (and vocal) fanbases of any franchise in gaming. How did you approach the community’s feedback when setting out to develop Borderlands 4?
Johnson: We take our fan community very seriously, and we listen. Of course, we don't make our feature or story decisions based solely on community feedback, because a million people can have a million differing opinions, and we have our own vision for the game. But we have been known to make course corrections when the fans make it known that something truly matters to them and when we agree. The recent, very late-production shift that added a combat radar to the HUD is the most recent example. I'm proud of that change and proud that we weren't afraid to make it.
What's the first thing you want players to think when they see Kairos in Borderlands 4 for themselves?
Johnson: I want them to think, 'wow, this world is gorgeous. I want to see what's over that hill.' I want players to feel that this game is a step change from the previous titles, with fewer of the obstacles to exploration that game constraints typically place on them. I want our players to feel that Kairos is a rich, lived-in world, even more so than Pandora and the other worlds from previous installments.
We've added so much more detail to this world than we could have done in the past. One example is the addition of "critters": small creatures that skitter about in the environment and give it more of a lifelike feel. These creatures don't have any impact on gameplay but their presence makes it feel more interesting and real.
Image courtesy of Gearbox Software, 2K Games
How does Unreal Engine 5 present the iconic Borderlands art style with even more graphical fidelity in Borderlands 4?
Johnson: Achieving the Borderlands art style brings challenges that other games might not have, and those challenges have only grown in recent years. These days, we have to deal with a multitude of rendering options including AI-driven upsampling, not to mention a wide range of screen resolutions and graphics card capabilities. The new GPU landscape and even the engine itself can sometimes present a challenge when it comes to achieving that beautiful inked look; advanced rendering features like Lumen sometimes force us to make trade-offs.
One thing I can say, though, is that Unreal's incredible Material system gives us the best tools in the industry to meet that challenge. Similarly, Global Illumination with fully dynamic lights has given us more control over our color palette and tone.
Our art team has incredibly exacting standards for that graphical art style, because it's part of the Borderlands core identity. I can say with confidence that they've been able to achieve their goals for that look with this engine.
What aspects of the UE5 toolset opened up new possibilities during development that weren't possible before?
Johnson: It's mostly an increase in scale that the new tools have given us. I mentioned how World Partition and One File Per Actor gave us the ability to build larger worlds. Similarly, Nanite allowed for more freedom to author meshes at the desired level of detail that our artists wanted. Lumen gave us more control over the rendered look of the game.In the area of gameplay, Blueprint is often cited as a powerful scripting tool, and here I want to say that we bucked the trend a bit by reining in the use of Blueprint as compared with our previous titles.
We learned the lesson that Blueprint is such a powerful tool that it needs to be used wisely, otherwise you can end up with scores of performance issues and difficult gameplay bugs late in the project. On Borderlands 4, we put 'guardrails' in place that forced Blueprint to be used only where we wanted it to. This unorthodox decision was one of the best things that we did on the project, allowing us to leverage Blueprint's awesome potential without hampering us.
Image courtesy of Gearbox Software, 2K Games
Borderlands 4 has a host of new movement abilities that let players zip around the battlefield by double jumping, gliding, dodging, grappling, and more. Were there any specific features of UE5 that helped you iterate on the feel and flow of movement in the game?
Johnson: Live Coding in conjunction with Play in Editor (PIE) allowed our gameplay programmers to do rapid iteration. It can take a lot of time to launch the game over and over again during development, as the engine has to load all of the world assets in their 'uncooked' form each time you launch. Being able to load those assets just once and then make repeated code changes afterwards that can be tested immediately in PIE saved us a lot of time. That improved iteration speed then resulted in better game features such as the ones mentioned.
Features such as the grapple system required hand-placement of 'grapple points' which themselves are custom Actor subclasses built by our gameplay coders. The other movement features relied on custom Character Movement Component changes in code. Because we have years of investment in the Unreal Engine, our coders and designers knew the right way to build those new movement features. Unreal augmented their capabilities rather than getting in their way.
Are there any new graphical details or visual effects made possible by UE5 that the team is particularly proud of? Could be anything big or small!
Johnson: Fully dynamic ‘time of day’ and weather come to mind. These were both possible before UE5, but they required many more hacks to fake global illumination, sky lighting, and atmospheric effects. Having everything start from a place of being dynamic and accurate to real-world physics made it far easier to achieve our quality goals.I’m also quite proud of the Echo-4 navigation feature, which draws a 3D path through the world to help players navigate. While more of a game feature than a graphics feature, it does rely on a Niagara beam effect. It’s only one effect among many, but Niagara’s flexible feature set allowed us to iterate on that effect to get it looking just how we wanted it to.
Image courtesy of Gearbox Software, 2K Games
Borderlands 4 offers a variety of ways to play either solo or with friends, including four-player online co-op and two-player splitscreen. How has UE5 helped you build the best Borderlands multiplayer experience yet?
Johnson: Here's where Unreal's feature set really shines. Gearbox has always been focused on providing the best co-op experience in the industry, and we simply couldn't do that without Unreal's replication and networking infrastructure. We've made our own modifications, especially to support splitscreen beyond what the engine supports out of the box; however, the engine gave us such a solid foundation of features that we could focus more of our energies on things like crossplay support rather than on the basics of getting hosts and clients to simply talk to one another.
Plus, Unreal's support for multiple platforms allows us to release Borderlands 4 on all the platforms that our customers want to play it on.
Gearbox, and I personally, have been using Unreal Engine for over 20 years now, and Unreal's online and networking features are what make it possible to make a game like Borderlands 4 and to allow our customers to play it with one another. We’re very excited to see where Epic takes this feature set going forward.
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To learn more about Borderlands 4, head over to the game’s official website.
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