When Tony Stark talks to Whiplash after the incident at the racetrack, he(Whiplash) has no legs. After Tony talks, if you look carefully, Whiplash has legs. I didn't know he had regeneration powers!
What are you talking about? At no point is Whiplash missing his legs. After being defeated on the track, he is dragged away by authorities (and his legs are clearly visible). When Stark confronts him in his holding cell, Whiplash is seated on a bench wearing only shorts--his hands are clasped together between his thighs. While the camera doesn't pan down to show his entire legs, he CLEARLY is not missing them.