The Inevitable, Explosive Return of Nitro!

While the man known as Nitro may have gotten off to a slow start as a presumed agent of the Lunatic Legion, he's unquestionably attained a lot of mileage out of his super-power, along with no small amount of notoriety. A villain who can detonate himself and reform at will, Nitro holds two main claims to fame (or, rather, infamy): being the catalyst for the events of Marvel's mega-event, Civil War (and, by extension, the Superhuman Registration Act), when he exploded in a populated area and caused over 600 deaths (including 60 school children)... and secondly, for precipitating the accident which resulted in the escape of deadly nerve gas that would eventually lead to the death of Captain Marvel.

Yet well before Mar-vell would become aware of his fatal diagnosis, he would meet Nitro again in battle, though not before the nascent hero named Omega the Unknown dealt him a setback:

Nitro, like the Sandman, Hydro-Man, et al. who have had their forms dispersed at one time or another, is well suited to being re-used as a threat in perpetuity without any major complications--brought into a story, apparently dealt with for good, and then inserted into another story at some future date.  (I.e., detonate, rinse, repeat.)  In Nitro's second meeting with Mar-vell, we only have to wait awhile until he can reassemble himself and return from the stratosphere--this time explosively impacting in the sheep meadow in Central Park, which is Nitro's way of surviving the fall back to Earth.

Apparently, Omega has been put on the back burner as far as Nitro's concerned.

As for Mar-vell, we catch up with him following his resolution to make a life for himself on Earth--and is he off to a good start on our planet. Look how quickly he gets the hang of taking what doesn't belong to him without recompense:

But he's not in civilian garb for long, since Nitro is intent on smoking him out. And where there's smoke--and a deafening explosion--there's in this case Nitro, who's crazed to deliver some payback to our hero.

For what it's worth to Nitro, Omega has met his death by this time, so that's one less thing on his sadistic to-do list. The question is, can Mar-vell put a halt to Nitro's current rampage and truly bring his threat to an end?

Without knowing it, Mar-vell takes a leaf from Omega's book, though with a clever twist--a way to partially contain Nitro's essence and thus nullify his ability to re-form.

Regrettably, Mar-vell has reckoned without the resourcefulness of an attorney working on behalf of Nitro's daughter, who has him freed from his subsequent incarceration at Project Pegasus. And taking a glance at the covers of the two respective stories 3½ years apart--in particular their "coincidental" issue numbers--writer Roger Stern seems to have stumbled upon an old Captain Marvel issue at just the right time for his Spidey story, eh?

BONUS!

Thirty-five years after putting this story to bed, writer Scott Edelman makes the connection between artist Dave Cockrum's last-minute substitution for the final page to this story by George Tuska and Captain Marvel's debut cover from 1967.