Recently closed Ensemble Studios was working on a Halo MMO, according to Gamasutra. Prototype UI and level screenshots have been uncovered from the project which lends much credence to rumors that circulated a while ago of Ensemble and Bungie working together on such a project.
The gossip was flying around as early as 2006 when talk of a Halo MMO first surfaced. No official announcement has ever been made, but this new evidence seems to suggest that the game was in development throughout 2006 and 2007 before being quietly canceled last year.
Of course, just because Ensemble isn’t working on it anymore, that doesn’t mean a Halo MMO is not being made. It’s quite clear that Microsoft wants to ride the Halo horse until its legs fall off, and MMOs seem to be the pinnacle of license flogging these days. I’ll be surprised if a Halo MMO doen’t happen in the future.
