Introduced with that dynamic Jack Kirby/Don Heck art in Journey Into Mystery 97 (Oct. 1963), the Lava Man stands out in my mind as a favorite among the thunder god’s early foes.
Remember the context of the times, an era in which — hard as it is to conceive now — real superhero slugfests were essentially something new.
DC’s heroes, in deference to that namby-pamby Comics Code, engaged in elaborate puzzle games with their bizarre enemies, finally dispatching them with a polite single-panel punch to the chin, or forgot about fighting crime while they created complex ruses to shield the secret of their identities.
But unlike DC, Marvel introduced fresh, public-panicking physical menaces each month, formidable city-smashing super-beings that required our heroes to defeat them in hand-to-hand combat.
Also, Thor had to face this destructive heat thing from the center of the Earth while troubled by the escalating soap operatic woes Stan Lee would invent for him. The woman he loves has walked on him, quitting her job as Dr. Blake’s nurse, and Odin has forbidden him to pursue her.
As in DC’s superhero comics, the villains return, but at Marvel the ante is often upped. Defeated the first time, a Dr. Doom or a Mr. Hyde will team up with a Sub-Mariner or a Cobra to make things much tougher for our heroes in the second round.
And six months later, in Avengers 5 (May 1964), the Lava Man would return with his entire tribe. I can remember thinking that if ONE Lava Man gave Thor a fight, what might a whole RACE of them do to the Avengers? I was excited to find out.
One other intriguing angle in Marvel’s plots was that heroes and villains didn’t always behave in perfectly predictable ways. They could grow and change. The Lava Man, for example, had learned respect for surface dwellers in his battle with Thor, and tried to argue his people out of their war on humanity.