Apple Inc. danger to revoke Epic Games Inc’s. developer account would have expansive impacts hurtful to the videogame industry, Microsoft Corp. said in a court filing Sunday.

The new filing by Epic comes in the midst of a strained standoff with Apple US:AAPL , which has evacuated Epic videogames, for example, the mega-popular “Fortnite,” from its App Store over a violation of its payment rules.

Epic contended that Apple’s danger to likewise block its developer account would keep other game developers from using its generally used Unreal Engine, which is used in the production of 3-D graphics, hurting “numerous third-party developers.”

Kevin Gammill, Microsoft’s US:MSFT general manager for Gaming Developer Experiences, concurred in an announcement of help, saying the boycott by Apple would put developers who use the Unreal Engine “at a substantial disadvantage,” since “there are very few other options available.”

“If Unreal Engine cannot support games for iOS or macOS, Microsoft would be required 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 said. “Apple’s discontinuation of Epic’s ability to develop and support Unreal Engine for iOS or macOS will harm game creators and gamers.”

Apple has said it will reestablish “Fortnite” and leave Epic’s developer account if the organization turns around course and follows to the App Store’s payment rules. In a filing Friday, Apple considered the effect on Epic a “self-inflicted” wound, and blamed it for purposely breaking its agreement after years of taking “advantage of everything Apple’s App Store has to offer.”