343i's Halo Reclaimer Trilogy, which began with the release of the fourth numbered entry in the series, has been expanded to be "more of a saga".
Speaking to GameSpot, Microsoft Game Studios corporate vice president Phil Spencer said the recent teaser featuring Master Chief is for a "legitimate" version of Halo for Xbox One, and the appearance of producer Bonnie Ross on stage at E3 was evidence of this.
"It is the next Halo game that we are working on," he said. "We will talk more about actually the story arc in the game and how it plays out; we've got more time to talk about that."
"But having [producer Bonnie Ross] come out and announce the game, making sure people know it's a legitimate version of Halo coming out, and when it's coming out, and features that they're focused on we thought was...important."
The Reclaimer Trilogy was originally announced as the moniker for Halo 4, Halo 5 and Halo 6 together. However, according to Spencer the scope of the project has widened.
"While we originally said trilogy, we've actually expanded this to more of a saga, so we don't want to limit the Reclaimer story within a trilogy."
Microsoft also recently showed off Halo: Spartan Assault, a top-down shooter for mobile devices and PC.