Reports are coming in from various sites, that the new Fable2 DLC: Knothole Isle, contains the assault rifle from the Halo series. Appropriately titled "Hals Rifle", it is designed to go with the limited editions Master Chief outfit. The gun can be found at "The Box of Secrets" store, you trade expierience extract for the weapon.
Update
UPDATE: Screenshots on site
UPDATE 2: Clear Screenshots and a video added
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