Issue(s): Tales Of Suspense #82, Tales Of Suspense #83 (Captain America stories only)
Cover Date: Oct-Nov 66
Title: "The maddening mystery of the inconceivable Adaptoid!" / "Enter... the Tumbler!"
Credits:
Stan Lee - Writer
Jack Kirby - Penciler
Frank Giacoia / Dick Ayers - Inker

Review/plot: Cap has World War II flashbacks...

...due to drugs that the Adaptoid (not "super" yet) slipped into Cap's coffee when he was posing as Jarvis.

With Cap passed out, the Adaptoid impersonates him. Then a loser called the Tumbler breaks into the Avengers mansion and attacks the Adaptoid, thinking it is Cap.

The Adaptoid has a hard time handling the Tumbler, causing it to doubt itself. The Tumbler actually beats the Adaptoid, just in time for the real Cap to wake up and free himself. He makes short work of the Tumbler.

John Seavy at MightyGodKing has a nice review of issue #83.

Quality Rating: C-

Historical Significance Rating: 5 - first (Super) Adaptoid

Chronological Placement Considerations: At this point SHIELD is aware that AIM is not on the up-and-up. Takes place after Strange Tales #148-149; see the Considerations on those issues for details.

References: N/A

Crossover: N/A

Continuity Insert? N

My Reprint: Marvel Double Feature #6-7

One of the Golden Age villains Cap sees in his hallucinations is Agent Axis, and his presence is an example of Stan and Jack having a bad memory simultaneously. Agent Axis did exist in Golden Age stories--but as a Boy Commandos villain created by Simon & Kirby for DC. Kirby forgot what feature he created him for, and since Stan didn't become EIC until Joe Simon quit Timely, he probably took Kirby at his word. In other words, Marvel swiped a DC character and got away with it. Agent Axis popped up in a few Invaders stories, and when DC used an Agent Axis of their own for World's Finest #250, they had to create a new one.

Cap also sees Warlord Fang, who was a genuine Timely villain, albeit called just the Fang. When Marvel reprinted the story in Fantasy Masterpieces, the Comics Code made them remove a tied-up lady from the splash page and take out the Fang's fangs. Interestingly, Cap says Fang died in Hiroshima--which he would have learned only after being defrosted, since he got frozen before V-E day in 1945.

Amazingly considering this is his first appearance (and he does have later ones...and a title in this issue), I'm surprised you didn't label the Tumbler...but as you said, he's a lame villain but at least he beat the Adaptor...well, the regular Adaptor.

Thanks Ataru. It's very likely just user error - especially on issues added earlier in my project before i religiously cross-referenced the MCP. But i am starting to suspect gremlins, like maybe i've hit some secret tag limit in my system and things are getting dropped randomly. I do have the Tumbler's second appearance tagged and also the appearance of the second Tumbler and both of those would have been an opportunity for me to notice that this issue wasn't tagged for him. Anyway, i've added him (back?) and will keep an eye out.

Judging from the recently released hardcover Boy Commandos V.2, it seems that Jack Kirby's memory was even worse than previously estimated--the Golden Age DC Agent Axis was actually female.

I don't think it had anything to do with anyone's bad memories. I think this a brand new character retrofitted into Cap's past as was Baron Zemo. The background to the character was later written up by Thomas in the Invaders. I like the Adaptoid a lot and Agent Axis as well. In my own stories, my counterpart to him is the Swastika.

Easy enough to check using GCD: http://www.comics.org/issue/70552/ lists Agent Axis as a villain in the story "Satan Wears a Swastika," from Boy Commandos #1, 1942.

First I used Wikipedia to get the issue number:
https://en.wikipedia.org/wiki/Agent_Axis

Wiki further agrees with your recollection regarding Baron Zemo, who they say first appeared in Avengers #4, 1964. Mark's comments seem to be meticulously accurate, and I recall reading something similar to his account somewhere, probably in one of Roy Thomas' fanzine articles, but I can't really recall where, due to my own spotty memory.