Leonard Morris Betts, played by Paul McCrane in the episode "Leonard Betts": Betts, born Albert Tanner, was a Pittsburgh EMT, and a mutant. His body was internally riddled with cancer, but this was actually his normal state of being. Leonard's body, as a result, could regenerate any lost body part, even a new head. To sustain his ability, he had to bathe in povidone-iodine...