The popular video game Fortnite was removed from Apple's App Store on Thursday, after Epic Games attempted to circumvent Apple's 30% cut of in-app purchases.
In response, the Cary, N.C.-based video game maker filed a lawsuit against Apple, asking a court to order Apple to reinstate the game and declare the Apple fee illegal.
In its legal filing, Epic said the removal of Fornite is "yet another example of Apple flexing its enormous power in order to impose unreasonable restraints and unlawfully maintain its 100% monopoly over the iOS In-App Payment Processing Market."
The ban came after Epic released its own in-app payment system on Thursday that would have bypassed the fees taken by Google and Apple's app stores.
The coordinated move and subsequent legal filing represent a significant uptick in the tensions between the two companies.
Epic's founder and CEO Tim Sweeney has long railed against these fees as being exorbitant and an unfair business practice. Apple has come under fire recently, both in the U.S. and in Europe, over antitrust concerns related to its mobile marketplace.
In its release, Epic Games told its users that using the in-app payment system rather than Apple or Google's would result in lower prices for them.
It offered 1,000 V-bucks -- about $10 worth of Fortnite's internal currency -- for $7.99 if a player used the direct payment system. Using the normal Apple payment system, the same amount of V-bucks would cost $9.99.
In a statement to the website The Verge, Apple said it removed the game because it violated its App Store guidelines.
"Today, Epic Games took the unfortunate step of violating the App Store guidelines that are applied equally to every developer and designed to keep the store safe for our users," the company wrote. "As a result their Fortnite app has been removed from the store. Epic enabled a feature in its app which was not reviewed or approved by Apple, and they did so with the express intent of violating the App Store guidelines regarding in-app payments that apply to every developer who sells digital goods or services."