Halo: Nightfall is available now on DVD and Shacknews has a pair of copies to give away.
Halo: Nightfall bridges the gap between Halo 4 and the upcoming Halo 5: Guardians. It follows the story of John Locke, a Spartan soldier that must hunt down and prevent Covenant forces from using a weapon that will only affect humanity. Viewers can get to know Locke before he and Master Chief cross paths in Halo 5, where one or the other is branded a traitor.
To enter, follow the Shacknews Twitter account and reply to this Tweet with your favorite Halo series moment. Alternately, you can reply to this Facebook post with your favorite Halo moment. One lucky winner will be drawn from Twitter and Facebook. (Open to U.S. residents only.)