Here is the list of free games available on the Xbox 360 and Xbox One to Gold Members only, for the month of December. Don’t forget you can save lots of money on Xbox Live Gold Membership and Microsoft credit here
On Xbox One, Xbox Live Gold members can download Warhammer: End Times – Vermintide for free during the month of December. Back to the Future: The Game – 30th Anniversary Edition will be available as a free download from December 16th to January 15th.
On Xbox 360, starting December 1st, Child of Eden will be free for Xbox Live Gold members through December 15th. Then on December 16th, Xbox Live Gold Members can download Marlow Briggs and the Mask of the Death for free through December 31st.
SOURCE : MAJOR NELSON