Epic’s legal fight with Apple over the future of Fortnite has quickly evolved into an existential battle for one of the game studio’s most lucrative and important assets: the Unreal Engine platform.
After removing Fortnite from the App Store, Apple targeted Epic’s other developer account tied to its game engine, putting at risk the company’s licensing business by threatening to cut iOS and macOS support. Epic secured a last-minute temporary restraining order late Monday evening to protect the business in the short term, but the fate of the Unreal Engine is still up in the air — endangering an entire ecosystem of third-party tools that rely on the engine.
As Epic warned in a court motion last week, Apple’s moves against the Unreal Engine would threaten the software behind “hundreds of video games, the human brain, Baby Yoda, and space flight.” Projects like The Mandalorian may have no obvious connection to Epic Games and Fortnite, but they rely on the company and its tools to do their work. And as Epic and Apple settle in for years of legal warfare, those sorts of projects are likely to be disrupted too.
Developed in 1998 alongside the first-person shooter Unreal, the Unreal Engine has become a cornerstone of Epic’s business and the gaming industry at large. It’s currently used by dozens of game makers, Hollywood production and special effects studios, and other firms in the 3D rendering and computer graphics businesses.
The engine is also how Epic builds its own games, including Fortnite and past major hits like Gears of War and Unreal Tournament. Scores of big-budget game makers have also forgone custom, in-house engines for Epic’s, like Gearbox Software (Borderlands 3), Riot Games (Valorant), and Square Enix (Final Fantasy VII Remake). Epic licensed the software to thousands of developers who don’t have the resources to build their own engine, in exchange for a five percent royalty on whatever’s created. That licensing has turned Epic’s Unreal Engine into a popular toolkit even for major, big-budget games, rivaled only by the more mobile-focused Unity.
Now, the engine is at risk of becoming collateral damage in the company’s fight over in-app payments in Fortnite. When Apple removed Fortnite by revoking Epic’s primary app developer account, it also planned to revoke the developer account Epic uses to maintain the Unreal Engine on iOS, as part of its policy of removing linked accounts after a breach of contract.
The court has restrained Apple from revoking that account for the next few weeks, but it remains to be seen whether it will keep the account protected for the full duration of the trial. (A temporary injunction hearing to settle the matter is scheduled for September 28th.) But if Apple prevails — either in the preliminary injunction or in the broader case — Epic’s testing tools for the Unreal Engine will suffer the same fate as Fortnite, cutting the system off from updates and broader development.
If Apple successfully fends off the injunction next month, the effect won’t be immediate, and games running on the Unreal Engine will keep working on iOS — at least until a major bug pops up. But the longer-term implications could be disastrous, especially for iOS game developers. Because Apple controls the process by which developers create, test, and then submit iOS apps and any future updates for review, Unreal’s inability to support the iOS platform means Epic can’t incorporate new features of the operating system or implement updates and bug fixes that a game developer might need to keep the product running and functional.
“If Epic lost access to Apple’s developer tools, that wouldn’t break any current apps using Unreal in the App Store (or on other platforms),” Riley Testut, a popular game emulation developer who now operates an alternative mobile app store called AltStore, tells The Verge. “The problem is more for developers going forward; if Epic can’t use Apple’s tools, they can’t release bug fixes or new features. This most likely would mean Unreal-based games would break eventually in future versions of iOS and macOS, and Epic would be unable to do anything about it.”
Microsoft raised a similar point in court, in a declaration submitted last week. “Developing a game using different game engines for different platforms may be prohibitively expensive and difficult. In any event, it is not as cost-effective as using a game engine that supports different platforms,” explained Kevin Gammill, Microsoft’s general manager for gaming developer experiences, in a declaration of support for Epic that Microsoft filed. As Gammill paints it, Apple terminating Epic’s account would force it to “choose between abandoning its customers and potential customers on the iOS and macOS platforms or choosing a different game engine when preparing to develop new games.”
Gammill specifically cited Microsoft’s Forza Street, a mobile version of its Turn 10 Studios racing franchise, as an example of a game that relies on iOS support in the Unreal Engine. “Even uncertainty about the Unreal Engine’s ability to continue supporting iOS and macOS will make it less likely for Microsoft (and, I believe, other game creators) to select Unreal Engine for their projects,” he wrote. “When game creators are planning development projects, which can last for years, it is important to have confidence that the chosen engine will continue to be available on and support all platforms on which the game creators plan to distribute their games.”
Unreal Engine is primarily used for the development of console and PC games, but it has a growing mobile business that’s become increasingly important as the game industry has shifted toward cross-platform play. Epic specifically touts a developer toolkit that works in tandem with Unreal Engine, called Epic Online Services, that allows games to take advantage of the technology developed initially for Fortnite. The engine’s cross-platform nature is a selling point that makes it one of the go-to platforms for building virtual worlds. Without an Apple developer account, Epic can’t promise developers interested in iOS any of those benefits, an unwelcome shock as its main competitor Unity prepares to go public.
In Monday’s hearing, an Epic lawyer argued that even just the threat of Apple terminating the account associated with the Unreal Engine has sent developers “fleeing” from the platform. “So far as Epic is concerned, the Unreal Engine will be actually destroyed. It will no longer be a usable engine,” argued Katherine Forrest of the law firm Cravath, Swaine & Moore, which is representing Epic in the case. “If Epic cannot offer that with the Unreal Engine, Unreal Engine will cease to exist. We’re receiving information from developers saying they’re fleeing the Unreal Engine now.”
For companies that are also building smaller, less graphics-intensive projects — like indie games — that can be ported to multiple platforms, the lack of iOS support for Unreal Engine would be a deal-breaker. For a game developer, switching to another engine often means scrapping almost every hour of work on an ongoing project and starting entirely from scratch.
The Unreal Engine is also increasingly important for Hollywood projects using real-time rendering. In particular, Disney and Lucasfilm have turned to Epic’s engine as a tool for filmmaking, using it to create virtual sets, characters, and animations for large Star Wars projects, including Solo, Rogue One, and The Mandalorian.
More than half of the first season of The Mandalorian was in fact shot using custom LED walls that displayed virtual sets, all powered by the Unreal Engine to allow the crew to see in real time what the shot was going to look like weeks and months before post-production and special effects teams finished the final product. Disney and Lucasfilm did not respond to a request for comment on how developing Star Wars projects may be affected by the ongoing litigation.
Unreal Engine is also used by automakers like Audi, Porsche, and Volkswagen to help design cars using visualization and other software processes. Architectural firms use the engine for similar reasons, allowing those companies to perform real-time visualizations of in-progress projects. Epic also licenses Unreal for broadcasting and live event production, with the engine capable of producing real-time graphics, overlays, and other real-time rendered assets.
One high-profile example is The Weather Channel’s now-viral mixed reality segments that blend the effects and visuals of simulated natural disasters around real-world hosts in the studio, all using Unreal Engine.
Many of those projects don’t require iOS functionality, but they may run their backend systems on macOS, which will be affected in a more limited way. Without macOS support in Unreal Engine, Epic loses access to macOS testing tools and the ability to issue speedy updates that may contain bug fixes and security patches. Apple also now requires notarization — in other words, Apple approval — of third-party apps even on macOS so long as they have a developer ID. Without that developer ID or notarization, Unreal Engine users would have to effectively seek out updates and click through security warnings Apple imposes upon third-party software it has not reviewed.
“Imagine losing access to your Google account, and everything that comes with it,” one iOS developer, who wished not to be named for fear of repercussions from speaking negatively about Apple, tells The Verge. “Apple’s very much moving to a Mac that requires software to be signed and notarized with Apple, and Epic would no longer be able to do that. Right now, trying to run unsigned software on the Mac shows scary warnings and can be sidestepped. In the future, not so certain.”
The developer says, like with iOS, the effects of losing macOS support won’t be felt immediately, but the risk might scare companies away. “Because of that uncertainty, developers would no longer be able to rely on Unreal Engine to support Apple’s platforms. For example, Epic would not be able to release their tools to support Apple Silicon, so effectively it would be the end of the line for Unreal Engine on the Mac,” they said.
It’s too early to tell whether the rhetoric of Epic’s legal team — and claims the Unreal Engine would be “absolutely destroyed” — is hyperbole, or whether Apple really does have the power to cut off a multibillion-dollar company at the knees by terminating a single developer account or even just threatening to do so. But Epic has committed to continuing its fight without walking back the Fortnite update that initiated its unprecedented showdown with Apple. And Apple, it’s now clear, is willing to do everything in its power to ensure Epic doesn’t blaze a trail other developers may be keen on following.