UPDATE: October's second free Xbox 360 game will be 2007 hit Halo 3, Microsoft's Major Nelson has just confirmed.
Bungie's sci-fi shooter will be available to download for free from 16th October, following the previously-announced Might & Magic Clash of Heroes.
Halo 3 was first tipped to be part of Microsoft's free Games with Gold promotion back at its unveiling, alongside Assassin's Creed 2.
ORIGINAL STORY: Xbox Live Gold subscribers will be able to freely nab Might & Magic Clash of Heroes from 1st October, Microsoft has announced.
Capybara's superb puzzle RPG will be available as part of the Xbox 360 Games with Gold promotion until 15th October.
Microsoft's offer gifts a new game every fortnight, and has so far included Assassin's Creed 2, Crackdown and Magic: The Gathering 2013.
Company mouthpiece Major "Larry Hryb" Nelson also revealed release dates for a handful of upcoming Xbox Live Arcade titles, including Toy Soldiers creator Signal Studios' free-to-play RPG Ascend: Hand of Kul.
Developed by Toy Soldiers creator Signal Studios, Ascend will launch tomorrow, alongside all-female brawler Girl Fight. PC platformer/shooter A.R.E.S. is next to arrive on 2nd October.