Sixteen months after announcing the game for the Mac and Windows platform, Bungie ships Halo as a launch title for the first edition of Microsoft's Xbox console, in the interim having been purchased by Microsoft. According to many reports, however, the game had been in development possibly since the shipping of Myth 2, putting the total development time at slightly less than three years.

If one disregards Oni, which was done in part by Bungie West and in part by the Oni team members brought to Redmond after the buyout, then the gap between Bungie's last release (Myth 2) and the release of Halo 1 is three years. The announcement bifurcates that period.