Other games have done similar things, like Gears of War and their guns magically attaching to their backs.
I have no idea, in one of the Halo 3 CGI trailers Chief attaches his assault rifle to his back and it makes a clicking sound, so I assume there is some sort of magnetic thing.
I'll admit I think it would be cool if the weapons had straps and would hand down the side of your back or something...
So I guess Chief's ultimate weakness would be a giant magnet?
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