Hellblade devs Ninja Theory now face closure after the failure of agreements with potential buyers, but Microsoft are "continuing to explore other paths".
Call of Duty company Activision are now in charge of Halo following Xbox cuts, with Halo Studios stripped and reduced to a support studio for existing games.
Microsoft-owned Xbox are reportedly set to lay off hundreds more staff and "consolidate" several game studios this week, in another round of major cuts.