Retro games have made a comeback in fashion. Over the past several years, many developers have made a name for themselves by releasing modified versions or collections or ports of high-quality classic games. These revivals go beyond just nostalgia, as they add visual improvements and gameplay enhancements for quality of life, as well as include museums filled with information about game creation. These re-releases benefit the video game industry, but there is a problem for developers: they require special technology.
Many of the studios behind these old revivals have created their own simulation engines to make the work they do possible. The KEX engine from Nightdive Studios and the Carbon engine from Limited Run Games may be the most famous, but the Eclipse engine from Digital Eclipse and the Syrup engine for subliminal transformations are also doing a great job. Without these game engines, recent re-releases like Death + Death 2, Little Witches, Lamasoft: Jeff Minter’s Story, and Tomba: Special Edition would not be possible.
I spoke to these developers to gain more knowledge about why they are creating these game engines and frameworks to revive old games. I found common threads in their responses. They all had a tendency to create modern frameworks that are easy to access and that can make old games look and feel at home on modern platforms.
KEX Engine – Nightdive Studios
Nightdive Studios has made a name for itself over the years by remastering classic first-person shooter games. Their latest release is Timespinner Remastered. In an interview following the release of Death + Death 2, Larry Kuperman, the business development manager at Nightdive, explained that the studio’s vision for remastering is that it “should look and feel the way you remember the original game’s look and feel.” I believe the main goal of any developer working on these old releases could fall short of that.
To achieve this vision, Nightdive created its own KEX engine. Xaser Acheron from Nightdive describes KEX as an “incredibly flexible” engine that allows Nightdive to essentially deliver the game they are remastering and work on types of integrations necessary to reissue a modern version of a classic game. Some, like Death + Death 2, even use the same game display device they are remastering, which is why they look very accurate compared to the original versions, even with all the enhancements made to them.
The KEX Engine also provides the studio with room to expand on these classics, whether through quality of life improvements, new content, or developer exhibition halls showcasing development content. It’s a constantly high-quality game engine. Kuperman says Nightdive has no plans to make it a more ambitious engine for new games anytime soon. Regardless, they are very effective in achieving Nightdive’s primary goal.
Syrup Engine – Implicit Conversions
Implicit Conversions, known for re-releasing PS Plus versions of classic PlayStation titles, created its own simulation engine. Called the “Syrup Engine,” a game that uses it was released this week. That game is Little Witches, originally designed for the NES but now available on the PlayStation 5, with added features such as online playrooms using rollback networks, widescreen support, rumble support, and more, all thanks to the Syrup Engine.
Robin Lavalley, CEO and co-founder of Implicit Conversions, told Digital Trends that the team needed to create their own engine because commercial emulators for consoles are rare, and those that exist “are usually protected by (non-disclosure agreements).” The Syrup Engine enables developers to bring old games forward with new features like widescreen support, save states, and more. It uses pre-compilation to accomplish this and features an automatic testing system that automatically captures screenshots of the games that have been emulated and compares them to reference screen shots of the original. Implicit Conversions aims to create an engine where developers do not face many obstacles when delivering games.
“I like to think of the Syrup Engine as trying to find its place, much like the way Unity, Unreal, GameMaker, and now Godot were created to enable thousands of game developers to create games,” says Lavalley. “It has democratized game development.” “We hope to achieve a similar goal for old and classic games by creating and providing technology that will allow game developers to efficiently move games through simulation.”
Eclipse Engine – Digital Eclipse
Digital Eclipse is known for the Gold Master series of video game bundles, which also serve as interactive exhibits providing historical context for notable games. To achieve this, Digital Eclipse uses an internally dubbed engine called Bakesale (named after the Bakesale Betty fried chicken restaurant in Oakland). This is publicly known as the Eclipse Engine, a framework that allows Digital Eclipse engineers to work within it to enhance old games for modern platforms or create entirely new versions of classic games like Tetris.
Editor-in-chief Chris Kohler for Digital Trends says: “It’s a framework that gives our engineers the tools they need to seamlessly integrate simulation technology from multiple sources, and then build on top of that.” “At its core, it allows us to integrate functions like save/load and rewind. Additionally, if you look at games like Yars’ Revenge enhancements in Atari 50: Anniversary Celebration, or Gridrunner remastered in Lamasoft: Jeff Minter’s Story, these are examples of how to add layers on top of the games that have been simulated to create an entirely new audiovisual experience while maintaining the core original game underneath.”
For Digital Eclipse’s efforts specifically, Kohler also explains that Bakesale has the internal tools necessary to enable their collection timeline. Designed specifically to meet Digital Eclipse’s specific needs, Kohler says Digital Eclipse does not need to “reinvent the wheel every time.” Each game is different, and resource developers may need to aid in remastering or reissuing. Technology like Eclipse Engine makes this complex process of creating something like Tetris Forever a bit easier.
Carbon Engine – Limited Run Games
Limited Run Games is a company at the forefront of modern physical releases and old classics revival. In recent years, they have been more actively involved in game development and publishing, restoring series like Rocket Knight for publishers with large catalogs of old games like Konami. They have done so using the Carbon Engine, which Joe Modzeleski, the development manager of Limited Run Games, describes as a “game development environment using simulator interface, modified read-only memory, custom front-ends with modern platforms” in a statement to Digital Trends.
Modzeleski wants Carbon Engine to provide developers “a way to use their old catalog without similar financial risks,” comparing it to their efforts in physical games. The Carbon Engine allows similar enhancements as seen from other engines on this list, such as widescreen support. Like every developer I spoke to about this, Limited Run Games wants to revive old games to be more achievable.
A representative from Limited Run Games says: “The cost of starting development and doing the foundational work to simulate a diverse range of old platforms on modern systems is a financially daunting task, and difficult to justify financially for individual titles.” “Providing an option where we have already done this foundational work has made it possible to bring back games that would not have happened otherwise.”
Limited Run Games may be the most ambitious among the developers I spoke to, expressing their intentions “to continue expanding the core systems supported by the Carbon Engine and make the development environment more suitable for use by our internal and external partners.” This approach ultimately sheds some light on why these simulation engines are increasingly common in games.
As more developers focus on simulation and remastering, any technology that allows them to avoid having to redo legal work for development and that can be shared across projects is a godsend. These engines work to improve game simulation safely while also adding modern quality of life improvements that make classic games better as well. The revolution of retro gaming has arrived, and these game engines provide enough power to ensure that this revolution does not end anytime soon.
