Adamantium caused Jack to lift an eyebrow as well. He tried to catch the Doctor's eye, wondering what the other man thought of that development. That was one of the last things Jack really wanted to hear -- particularly if it was in that. Jack's eyes fixated on the claw, arching a brow as if to say 'impressive'.
Jack knew the death of his that would beat them all, but it was one of those things he didn't like bringing up. Hell, it was one of those things he had hoped to keep from Ianto for a good long time. He'd never explained why the Daleks spooked him so when they had shown up, why there had been a look of pure panic on his face. But... Jack drew in a breath. If he wanted to win, he would have to divulge all.
"The worst creatures you could imagine. Aliens, though that may be too kind. They're known across the galaxies as the Daleks." Jack's gaze flicked quickly towards the Doctor, ignoring Ianto for the time being. "They say very little, but when they say 'Exterminate', that's it. Game over. And being the last man standing, facing down the entire army of 'em."