Frankie's guide to dual wielding at Bungie.net, published on October 26, revealed that there is at least one Covenant weapon that has not yet been revealed, and that it is dual wieldable. No other information is currently available.
Magazine articles have referred to a weapon called the "beam rifle" which may be separate from the Plasma Rifle and the Covenant Carbine, and has also not yet been seen. It may or may not be the unrevealed dual wieldable weapon to which Frankie refers.
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