Interview
December 2, 2025
Clair Obscur: Expedition 33: autonomy, creativity, and community key to Sandfall Interactive’s success
As the calendar year comes to a close, it’s a time for recognition and reflection. For the small team at Sandfall Interactive however, it’s also the culmination of an unforgettable journey surrounding one of the year’s most celebrated games—Clair Obscur: Expedition 33.
The compelling turn-based RPG defied the odds by becoming one of the most well-reviewed and commercially successful titles of 2025, racking up numerous accolades in the process—including a record-breaking 12 nominations at The Game Awards in categories such as Best Game Direction, Best Role Playing Game, and even Game of the Year.
Although this success is relatively recent, Sandfall’s development journey started many years ago. Co-Founder, CTO, and Lead Programmer Tom Guillermin’s journey of personal growth as a developer—and his deep connection to Unreal Engine and its community—began with humble roots.
In this interview, we explore how he got started and how the evolution of Unreal Engine coincided with the growth of the team at Sandfall. We also dive into how key UE5 features such as Nanite, Unreal Insights, and Blueprint visual scripting impacted development for the growing team.
Although this success is relatively recent, Sandfall’s development journey started many years ago. Co-Founder, CTO, and Lead Programmer Tom Guillermin’s journey of personal growth as a developer—and his deep connection to Unreal Engine and its community—began with humble roots.
In this interview, we explore how he got started and how the evolution of Unreal Engine coincided with the growth of the team at Sandfall. We also dive into how key UE5 features such as Nanite, Unreal Insights, and Blueprint visual scripting impacted development for the growing team.
A true passion project
Every journey begins with a single step and for Guillermin, his experience with Unreal Engine is no different.
“The very first time I explored Unreal Engine was actually Unreal Engine 1 a long time ago,” he says. “I was playing with a map editor from Deus Ex, an old game, to create some levels and to do a little bit of scripting and placing of game objects. It took many years before I actually dove into creating my own games.”
Learning any game engine takes time, but Guillermin soon discovered a passionate community of likeminded Unreal Engine developers posting tutorials, tips, and tricks on YouTube. “It's very open, very positive,” he says. “The community is dedicated to Unreal. You can really tell there is a love for the engine.”
Clair Obscur: Expedition 33 © 2025 Sandfall Interactive.
Guillaume Broche, Co-Founder and CEO of Sandfall, and Creative Director on Clair Obscur: Expedition 33, had previously explored other game engines. “But when he looked into Unreal, it was love at first sight,” says Guillermin.
As the duo continued to investigate Unreal Engine, their interactions with the community increased and, as a result, the sharing of knowledge became a central component of the team’s growth. “I think it really shows in the way people are sharing tips and tricks or just showcasing projects,” he says. “This is something we try to contribute to in our own way. For example, with MetaHumans, we were among the first to put YouTube videos online.”
These community interactions—in parallel with their personal growth as developers—produced a forward momentum that has carried their project through to completion.
As the duo continued to investigate Unreal Engine, their interactions with the community increased and, as a result, the sharing of knowledge became a central component of the team’s growth. “I think it really shows in the way people are sharing tips and tricks or just showcasing projects,” he says. “This is something we try to contribute to in our own way. For example, with MetaHumans, we were among the first to put YouTube videos online.”
These community interactions—in parallel with their personal growth as developers—produced a forward momentum that has carried their project through to completion.
Finding a Blueprint for collaboration
The team knew the engine had a supportive community around it, but did it have the technical capabilities they needed to deliver the project? It turned out the answer was a resounding yes. And one feature in particular highlighted the point.
“Guillaume is not a programmer—he doesn't know how to do C++,” says Guillermin. “But it was important to enable him to work on the project.”
Clair Obscur: Expedition 33 © 2025 Sandfall Interactive.
Unreal Engine’s Blueprint visual scripting system proved to be the perfect tool to bridge the gap between the two roles. “All the core logic of the game actually ended up being Blueprints—even the features entirely made by programmers,” says Guillermin. “It was a faster way for us to innovate on the gameplay instead of trying to iterate on the heavy technical stuff that we just didn't have the manpower for.”
In this way, Blueprint enabled the entire team to contribute to the game. “As we moved forward and the team grew, everybody was Blueprint-fluent and they would contribute directly in the code logic,” explains Guillermin. “Everybody had a lot of freedom to do their job thanks to that particular tool.”
While Blueprints empowered every team member to take part in development, it was Sequencer that really brought their efforts together.
“Every single move in the game, during battle in particular, is a level sequence,” explains Guillermin. “As soon as you have a level sequence playing, the game designers, VFX artists, and sound designers have all the locations of everything they need to put projectiles or VFX on or animate. Everything can be perfectly in sync and I think it was a huge factor of autonomy and creativity for everybody on the team.”
In this way, Blueprint enabled the entire team to contribute to the game. “As we moved forward and the team grew, everybody was Blueprint-fluent and they would contribute directly in the code logic,” explains Guillermin. “Everybody had a lot of freedom to do their job thanks to that particular tool.”
A serendipitous sequence of events
While Blueprints empowered every team member to take part in development, it was Sequencer that really brought their efforts together.
“Every single move in the game, during battle in particular, is a level sequence,” explains Guillermin. “As soon as you have a level sequence playing, the game designers, VFX artists, and sound designers have all the locations of everything they need to put projectiles or VFX on or animate. Everything can be perfectly in sync and I think it was a huge factor of autonomy and creativity for everybody on the team.”
Clair Obscur: Expedition 33 © 2025 Sandfall Interactive.
For Guillermin, one of the best parts of the development process was growing their project alongside Unreal Engine itself, with numerous features and updates opening up doors and keeping their small team moving forward. “When we started developing, Expedition 33 was still using Unreal Engine 4, but the engine was always providing updates every few months.”
Previously, when navigating through a level, the game would freeze a little as it loaded the next area.
World Partition changed all that for Sandfall. It automatically divides a large world into a grid of streaming cells, with each cell containing a portion of the world’s actors and content. The engine then loads and unloads these cells dynamically based on the player’s position or other streaming logic—without the developer having to manually set up streaming levels.
Previously, when navigating through a level, the game would freeze a little as it loaded the next area.
World Partition changed all that for Sandfall. It automatically divides a large world into a grid of streaming cells, with each cell containing a portion of the world’s actors and content. The engine then loads and unloads these cells dynamically based on the player’s position or other streaming logic—without the developer having to manually set up streaming levels.
Clair Obscur: Expedition 33 © 2025 Sandfall Interactive.
World Partition enabled multiple artists to work on different parts of the world simultaneously—with only relevant parts of the world loaded, keeping memory and CPU/GPU usage optimal.
“Even though we have a small environment team—between three and five people depending on the development phase—locking a full level to work on it is a huge contention point,” explains Guillermin. “So having that technology was good for us, both in terms of performance but also workflow as a team.”
Flagship features of Unreal Engine 5 came into play as well. “As a small team, you don't have all the resources to create all the levels of LODs manually,” says Guillermin. “Nanite made our artists’ lives much simpler.”
“Even though we have a small environment team—between three and five people depending on the development phase—locking a full level to work on it is a huge contention point,” explains Guillermin. “So having that technology was good for us, both in terms of performance but also workflow as a team.”
Flagship features of Unreal Engine 5 came into play as well. “As a small team, you don't have all the resources to create all the levels of LODs manually,” says Guillermin. “Nanite made our artists’ lives much simpler.”
Clair Obscur: Expedition 33 © 2025 Sandfall Interactive.
Of course, optimization and performance play a key role in the end-user experience, and UE’s built-in tools assisted the team at Sandfall with delivering on their vision. “People are happy with the performance of the game. We're still working to improve that and Unreal Insights has been our key tool,” says Guillermin.
Guillermin has some candid advice for those assessing an engine for their first (or next) project. “The most important thing is what type of content you want to create,” he says. “Sequencer was key for us, because we knew we would have so many cinematics and the characters would be important. If we were to choose an engine today, MetaHuman would be one of the key factors pushing us towards Unreal.”
Choosing an engine
Guillermin has some candid advice for those assessing an engine for their first (or next) project. “The most important thing is what type of content you want to create,” he says. “Sequencer was key for us, because we knew we would have so many cinematics and the characters would be important. If we were to choose an engine today, MetaHuman would be one of the key factors pushing us towards Unreal.”
Clair Obscur: Expedition 33 © 2025 Sandfall Interactive.
Guillermin also notes that each engine is different and it’s important to feel comfortable in the one that you choose. “For us, it was Unreal,” he says. “We were really happy with the way it allowed us to grow from a one-person project to two or three, and then to an actual team and on to shipping a game.”
As he points out however, the engine is just one part of the puzzle. “Another important thing is to look at the whole ecosystem around the engine,” he says. “You have learning resources, but you also have all the marketplaces that are tied to the different engines. And in the case of Fab for Unreal Engine, it has been super useful to get either free or paid assets.”
With the game having shipped and the industry responding to their project in such a positive way, the team at Sandfall seems simultaneously humbled by and proud of their achievements.
“We are really excited to see what will be happening at The Game Awards, because there are so many other great games nominated next to us—many of them we actually look up to as a source of inspiration,” says Guillermin.
As he points out however, the engine is just one part of the puzzle. “Another important thing is to look at the whole ecosystem around the engine,” he says. “You have learning resources, but you also have all the marketplaces that are tied to the different engines. And in the case of Fab for Unreal Engine, it has been super useful to get either free or paid assets.”
Recognition and reflection
With the game having shipped and the industry responding to their project in such a positive way, the team at Sandfall seems simultaneously humbled by and proud of their achievements.
“We are really excited to see what will be happening at The Game Awards, because there are so many other great games nominated next to us—many of them we actually look up to as a source of inspiration,” says Guillermin.
Clair Obscur: Expedition 33 © 2025 Sandfall Interactive.
“We could have never imagined the amount of success and love we're getting from all over the world, so thank you to all the players,” he continues. “As developers of something creative that we put a lot of ourselves into, seeing that it brings emotion to people is the most beautiful thing we can imagine.”
If you’d like more insight into how Clair Obscur: Expedition 33 was developed using Unreal Engine 5, check out our in-depth development interview here. If you want to learn more about the game, you can go to expedition33.com for all the latest.
If you’d like more insight into how Clair Obscur: Expedition 33 was developed using Unreal Engine 5, check out our in-depth development interview here. If you want to learn more about the game, you can go to expedition33.com for all the latest.