Back in the game? Microsoft sells Xbox One for $399

Microsoft kicks off E3 with focus on content

With Sony's PlayStation outselling Microsoft's Xbox One, the pressure is on for Microsoft to show it has the new games—and enough exclusive content—to boost sales of its console.

On Monday, Microsoft started selling its Xbox One unbundled from the Kinect motion-control software, for $399, a move to close the gap with Sony, whose next generation console sells for the same price. The announcement was made at the gaming industry's E3 conference.

"You have to start with the core customer of the box, which I think is that gamer," Xbox chief Phil Spencer said in an interview immediately following the presser. "We've architected the box for TV and all forms of entertainment...but we know that day one customer has to be the gamer, you expand from that gamer out."

The first big headline out of the conference was about Activision's upcoming "Call of Duty: Advanced Warfare," which will have digital add-on content.

Also at E3: A first peek at Ubisoft's "Assassin's Creed Unity." The new installment of the franchise will be available on the Xbox One. There was also a big focus on exclusives, such as Ubisoft's "Dance Central: Spotlight" for the XBox, which will go on sale this fall.

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But the biggest focus was on Microsoft's signature franchise: "Halo." The game studio offered a look at the upcoming "Halo: The Master Chief Collection," which will include the full story of the Master Chief—all five games—on one console for the first time. That means Microsoft is re-rendering the old games to make them compatible with Xbox One. A live action digital series, "Halo: Nightfall," will debut this fall and be included with the collection.

"['Halo' is] a unique thing you can only find on Xbox," Spencer said.

The addition of digital add-ons is a big win for the company and the gaming industry, he added.

"It's nice for our industry because now instead of just a big retail beat when you come out with a game, you can actually get revenue on a game over multiple years by continuing to deliver content. It's a healthy thing for the industry," he said.

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Microsoft didn't reveal any new sales numbers for its Xbox One, but the company said that since the console launched this past fall, the Xbox Live community has spent an average of five hours per day per console—nearly 1.7 billion hours on games and entertainment.