Microsoft's Electronic Entertainment Expo showing next week won't include everything the publisher has to offer. Executive Phil Spencer has said on Twitter that the company has more Xbox exclusives to announce after the show and potentially during Gamescom in August.
The Xbox maker has 15 Xbox One exclusives in development, eight of which are all-new franchises.
Spencer also continued to tease that Microsoft will make a surprising Xbox 360 announcement during E3 next week.
"Definitely have an announce that no one has guessed," Spencer said. "Let me know after the show if it was a surprise."
Spencer first talked about this Xbox 360 announcement last month after the Xbox One announcement event. At the time, he explained that the Xbox 360 has many years of life left.
"I think the [Xbox 360] is going to be very vibrant for many years. In fact, we have a huge, I think it's huge, [Xbox 360] announcement for E3 that I keep wanting to talk about, but I can't," Spencer said. "I think it will surprise people."
The company earlier this week announced Fable Anniversary for the Xbox 360.
Microsoft's E3 2013 briefing takes place Monday, June 10 at 9:30 a.m. PDT. GameSpot will be on-hand at the event.