Introduced as a one-off character in a 1942 issue of Hillman Periodicals' Air Fighter Comics (before it was re-named Airboy Comics), Harry Stein and Mort Leav gave us the mossy swamp monster known ...

The formula, which is drenched all over his body, then affects the plant in the swamp, imbuing it with Alec's consciousness and transforming him into an anthropomorphic mound of mossy matter.