The $68.7 billion gaming mega-merger between Microsoft and Activision Blizzard is facing in-depth competition scrutiny in the European Union.

EU regulators had been taking a preliminary look at the proposed deal, after the transaction was notified to the bloc's regulators at the end of September. But today the Commission confirmed it will open a deeper probe -- following in the footsteps of the UK's antitrust authority which announced its own in-depth investigation back in September.

In a statement today, the Commission said it's concerned the proposed acquisition could reduce competition in the markets for the distribution of console and PC video games and also for PC operating systems -- with the risk of driving up prices and reducing quality and innovation for consumers. "The Commission's preliminary investigation shows that the transaction may significantly reduce competition on the markets for the distribution of console and PC video games, including multi-game subscription services and/or cloud game streaming services, and for PC operating systems," it wrote.

"The preliminary investigation suggests that Microsoft may have the ability, as well as a potential economic incentive, to engage in foreclosure strategies vis-à-vis Microsoft's rival distributors of console video games, such as preventing these companies from distributing Activision Blizzard's console video games on consoles or degrading the terms and conditions for their use of or access to these video games."

"When it comes to multi-game subscription services and/or cloud game streaming services in particular, the Commission is concerned that, by acquiring Activision Blizzard, Microsoft may foreclose access, to the detriment of its rival distributors of console and PC video games that offer such services, to its own PC and console video games, which are key for the provision of the nascent services of multi-game subscription and cloud game streaming," it added, noting that it is particularly concerned of the risk of foreclosure affecting "high-profile and highly successful games" (so-called ‘AAA' titles) -- such as Activision Blizzard's ‘Call of Duty' franchise.