(Bloomberg) -- Google ramped up its antitrust battle with Epic Games Inc., countersuing the game maker for launching its blockbuster Fortnite game last year on Android and sidestepping the Google Play billing system.

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Google claims Epic intentionally breached its developer contract by updating Fortnite in 2020 with a “hotfix” to avoid paying Google Play developer fees and unjustly enriched itself at Google’s expense. Moreover, Epic went forward with its launch potentially at the cost of user security, Google said.

Google, which is seeking compensatory and punitive damages, said it lost global service fees as a result of Epic’s breach of contract.

“The Google Play ecosystem has suffered injury because the hotfix potentially exposed a security vulnerability that could be exploited for even more nefarious purposes,” Google said.

Epic continues to breach its contractual obligations as gamers who downloaded the “unapproved” version of Fortnite can still make in-app purchases through Epic’s payment system outside Google Play, according to the complaint.

Epic declined to comment on the lawsuit.

Epic separately sued Apple Inc. and Google last year, accusing them of maintaining a duopoly on mobile-app distribution with their app stores. Apple’s business model that includes collecting a commission from app developers was largely vindicated in a judge’s ruling in September following a trial in May, though the judge did somewhat loosen Apple’s grip on its App Store rules.

The Google case isn’t as far along. Just as Apple did, Google is now bringing counterclaims against Epic.

Google also faces a sweeping complaint filed in July by attorneys general of three dozen states, alleging that the company unlawfully abused its power over the sale and distribution of apps through Google Play.

The case is Epic Games Inc. v. Google LLC, 3:20-cv-05671, U.S. District Court, Northern District of California (San Francisco).

(Updates with details from filing, Epic comment)

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