It has been rumored quite a few times already that while Bungie may be taking a break from the Halo franchise, it doesn't mean a fourth installment is out of the question. On the contrary, Brothers in Arms developer Gearbox Software, who ported the original Halo to PC, is said to be secretly working on Halo 4. According to The Space Oddity the game will be a prequel, possibly titled Halo: Forerunner, and an announcement is to be expected very soon.
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