Deeply ingrained skepticism made Tony raise an eyebrow at that explanation, though he certainly couldn't argue the first part. He'd seen himself that Wally could move faster than should be possible within the bounds of human athleticism; doubting that now would be both ridiculous and counterproductive. He nodded slowly, processing the information and filing it away.

"An accident, huh? That's different." Tony gave Wally an odd, wry little smile. "I was figuring you might be a mutant." He realized almost immediately that the remark, if they really were from different worlds, might fail to make any sense at all. Even if the phenomenon existed, it might have a different designation. "Uh, we have people in my world who've got strange abilities, too. Genetic quirk, mostly. I'm not a biologist, I don't know the specifics."