Challengers of the Unknown #60

A massive, scaly creature dominates this March 1968 DC cover, its body mid-transformation as it shifts from monster to man — a genuinely unsettling sight rendered with real dramatic flair by cover artist Bob Brown. The yellow-suited Challengers recoil in the background, clearly shaken by what they're witnessing, while a speech bubble teases "It's ch-changing… to a man! And do you… see who it is!?" "The Thing That Could Not Die" sets up a mystery that's hard to put down before you've even opened the cover.