"It doesn't have to be iron."
The FBI agent ziptied to the table grunts.
"The process was initially designed for silicates, actually. But one tabloid hack calls you the Steelman—" and Steelman shrugs. "It doesn't hurt to have people assume, really, you know? There was some guy last year all I am your nemesis, Steelman! Behold my power of magnetism! and. Well. He's probably in your records, I guess."
He lifts the agent's gun thoughtfully to his lips, closes his mouth gently around the top of the barrel. Slowly, without pressure, his mouth closes, lips sinking through the metal; and he lifts his mouth away, neither chewing or swallowing, just rolling his jaw a little. The perfect cartoon-bitemark arc taken out of the gun gleams mirror-bright.
"I have been experimenting, pushing the nanites to synthesise more complex objects. A good mix of elements helps. And of course, if you have chemicals you can have electricity." Dark shapes begin to cloud under the skin of his hands, pushing through into three dimensions. "My guy Joey was kind enough to let me eat and extrude a copy of his taser a few times, which went fine, but I think I'm ready to try out a more original design." The lines of his armour plating shift under his parka, and he flexes his fingers experimentally, looking at the new blunt caps on his fingers, with their bright metallic contact strips.
"Good help's too hard to find to waste on calibration," Steelman says seriously, pushing his chair back; and begins to walk around the table to his captive.