The US government didn’t let Microsoft buy Activision Blizzard without a fight, although the Federal Trade Commission’s lawsuit to block the merger ultimately failed. Earlier this month, the FTC took aim at Microsoft again with a filing in federal court that claimed the new Xbox Game Pass tier was a “degraded product.” Now, Microsoft is firing back.

Via Game Developer, Microsoft responded to the FTC with a court filing of its own that was posted online by The Verge’s Tom Warren. The short version is that Microsoft acknowledges that the new Game Pass Standard tier is more expensive than the discontinued Game Pass Console tier, but it also offers multiplayer functionality that was previously sold separately. Additionally, the company argues that Game Pass Ultimate’s price increase is justified because more new games will be available day and date on the service.

Essentially, Microsoft is claiming that the the FTC is trying to “reinvent” its case against the company’s Activision Blizzard acquisition, and that it’s “wrong to call this a ‘degraded’ version of the discontinued Game Pass for Console offering.” The filing also notes that the FTC “barely mentioned subscription at trial” and restates that Microsoft signed a 10-year deal with Sony to keep Call of Duty on PlayStation as part of the original conditions for the merger.

So far, the federal court hasn’t weighed in on the FTC’s filing or Microsoft’s response. It seems unlikely that the Activision Blizzard merger could be easily undone at this point. But it remains to be seen if the court will take a side in the latest battle.

Meanwhile, the first Call of Duty game is on the way to the subscription service, as Modern Warfare 3 releases for Game Pass on July 24.