One of the Atlas series that got stuck in my imagination was Morlock 2001, the story of an artificial man who transformed into a plant monster. This is a sketch of the monster.
I never actually owned any Atlas comics. My allowance didn’t have room for them. I read, or more properly, looked through them, on comics racks during the scant 4 or 5 months that the company was publishing. Reading the plot descriptions for Morlock 2001 over at the Atlas Archives makes me wonder if I would still find the character fascinating if I’d owned and read the comics. Seems like a depressing series.