SSERPO!

By Stan Lee, with Kirby/Ayers art. Ayers remains among my favorite Kirby inkers, for all the monster, war, western and romance stories
where he inked Kirby's art from 1960-1963, and on FF 6-20 (issue 5 was inked by Sinnott, 1-2 by George Klein, 3-4 by Sol Brodsky).
And Ayers inked the 1st issue of AVENGERS.
Ayers also inked SGT FURY issues 1, 2, 3, and 13 over Kirby (1963), before taking over as penciller of that series for close to 20 years.

"SSSERPO!" appeared in AMAZING ADVENTURES 6, Nov 1961 (cover dated the same month as FANTASTIC FOUR 1)

Kirby's pre-Marvel monster stories (and likewise the Ditko stories of that era, circa 1958-1963) remain among my favorites of his work.

Full story at:
https://marswillsendnomore.wordpress.com/2012/12/23/jack-kirbys-monsters-sserpo/

In a larger more readable size:

AMAZING ADVENTURES 6 cover
page 1
page 2
page 3
page 4
page 5
page 6
page 7
page 8
page 9
page 10
page 11
page 12
page 13
With links to more pre-Marvel Lee/Kirby stories.

A rare treat in that era was the occasional Kirby/Ditko art combination. The last Kirby/Ditko story I'm aware of is FANTASTIC FOUR 13,
introducing the Watcher, and the Blue Area of the moon, some of which is reproduced by Byrne/Austin in the famous conclusion to the
Phoenix storyline in X-MEN 137 in 1980.