Halo 4 is in development at Gearbox Software and is is planned to launch alongside the Xbox 720, going by a rumor published in the latest issue of Official Xbox Magazine, as relayed by Joystiq.
Gearbox, which is wrapping up the WWII shooter Brothers in Arms: Hell's Highway (PC, PS3, 360) and the maraca-shaking music game Samba de Amigo (Wii), recently teased that it was working on a "big" project.
"It's big. It's, like, look-at-our-line-up-and-imagine-something-even-bigger kind of big," Gearbox president Randy Pitchford wrote on the company's forum back in February. When you find out what this is, you'll likely agree that I can't oversell this on...
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