Okay, if we're talking undervalued key issues, that incorporates comics at certain grades as well, despite if the comic key issue itself is already known. If we're talking about sleepers, that means comics that are keys that aren't well-known and not that sought after. That means bottom of the barrel comics...at least for now. Remember, what's considered bad yesterday just may be good today.
This Undervalued Comics and Sleeper Key Issues list will be a collection of both, just to be clear on that front. I have to apologize it may seem redundant. I will most likely be repeating myself quite often on this list. I will try to mix it up as much as possible.
Rom Spaceknight #1, December, 1979
- First appearance of Rom
- First appearance of Spaceknights
- First appearance of Dire Wraiths
The Rom comic series was actually the first comics I ever read. No joke. Little did I know that it was a Parker Brothers toy before it was a comic book, first named COBOL after the program language. It was later changed to ROM, which stands for read-only-memory.
When Rom was finally licensed to Marvel Comics, an origin, universe, supporting characters and villains were created. This is a serious sleeper bronze age key issue. Not that popular in comic world, even though Rom was set in the MU.
The comics are actually extremely under-rated, the stories are pretty damn good, and I always thought this character would be an awesome one to translate to the big screen.
This comic for CGC 9.6s are still dropping below the $100 mark for auctions. CGC 9.8s are below the $300 mark. Average sale is around $250 for 9.8s. High grade unslabbed copies are extremely affordable for the first issue and first appearance of Rom Spaceknight.
eBay
- Quite a few 9.8s and CGC options. Also, quite a few high grade raw copies to choose from as well.
2001: A Space Odyssey #8, July 1977
- First appearance of Machine Man (Aaron Stack)
X-51 or Machine Man makes his first appearance in this issue. Though created by the legendary Jack Kirby, Machine Man isn't really a mainstream comic character.
This issue is not that well-known and could be considered a sleeper for unslabbed, raw copies. Not an easy find as well. CGC graded copies in the higher realm are dropping for quite a bit of money, but this is still a bottom of the barrel key bronze age issue. Demand isn't that high for this book, but it's starting to simmer up.
eBay - Unslabbed options only at the time of this writing. There have been a few CGC copies that have come and gone. Most CGC copies are still under a hundred bucks. 9.8s aren't that easy to hunt down at the moment.
The Flash #1 Volume 2, June 1987
- First Flash series staring Wally West as Flash
Hello again! This comic was on my Flash key issues list, and although it's widely known as the Flash comic series where Wally West takes over - Barry Allen supposedly died. This is the first issue to Flash volume 2, and a so far under-valued #1 copper age key.
This sucker is still going for under a $100 bucks at CGC 9.8s, but high grade raw copies are dropping for much less. In a time where Copper Age keys are being mined vigorously, this Flash key has been overlooked for now.
That could change if they do decide to use Wally West in the Justice League movie instead of Barry Allen.
eBay - No CGCs at the time of this writing, and only a handful of unslabbed, raw copies. Some of them are in comic lots. May be one to look out for at your local comic shop or at a comic con.
ComicConnect - Flash #1 CGC 9.8 here for only $65 bucks if you're looking for high grade CGC under the $100 mark. You will have to scroll down to find it.
The Infinity Gauntlet #1, July 1991
- First issue to limited series
This is one of the best cross over series of the time. It's not that widely known, but many are speculating that the Avengers movie franchise could be leading up to a film that heavily borrows from the Infinity Gauntlet story line.
Written by Jim Starlin the creator of Thanos, the character is heavily used in this limited series and is the main villain. This copper age key issue is surprisingly still under the radar and is dropping for under $100 bucks at CGC 9.8s.
eBay - No problem finding this beast unslabbed or slabbed here. Saw a few CGC 9.8s newly listed and starting out at .99 cents. May get a high grade one for uber cheap.
Captain America #186, June 1975
- True origin of The Falcon
Taken from the Captain America key issues list Part 8, this is a sleeper issue and greatly over-looked as well. In this issue, The Falcon gets retconned by writer Steve Englehart.
In the earlier comics, Sam Wilson's origin was that of a social worker
who sought to better the lives of inner city youths. In this new retcon,
Sam Wilson's true past was that of a mob-connected thug and pimp. It
was revealed in this issue that the Red Skull used the Cosmic Cube to alter the memories of Sam Wilson, and he was indeed a criminal before becoming The Falcon.
Sadly,
this is known in the industry as the true origin of the Falcon. This is
still a bronze age key issue to get concerning The Falcon, and it is a
sleeper!
eBay - No CGC for this sleeper key issue, and only a handful of unslabbed copies. Most are in comic lots. Also another comic to see if your local shop has it in the back issue bin.
Terminator: The Burning Earth #1, March 1990
- First published comic art by Alex Ross
Published by Now Comics, this is the first published comic book artwork by Alex Ross, whose pretty amazing artwork, paintings, have graced many comic book covers since then. He has gone on to do covers for both Marvel and DC Comics, but his main work has been mostly appreciated by DC Comics and DC fans.
A pretty well-known comic and for it's key issue status, but highly over-looked and under-valued. CGC 9.8s can be snagged for under $100. Still a Copper Age book.
eBay - Not many CGC options. Only 3 and two are Signature Series. One SS is a 9.6 and the other a 9.2. Both are signed by Alex Ross. 9.6 is at $130. Loads of raw copies, and most are probably in high grade as well.
mycomicshop - More unslabbed copies. Highest is a VF.
Part 2 with more undervalued and sleeper key issues is ready. Just click the NEXT link below to continue!
I'll surely be looking for this key issue raw as a short term comic investment and most likely trying to hunt for it at my local stomping grounds. For now, short-term because the value staying constant or increasing depends on the success of the show. It does actually sound really interesting, about a girl who turns into a sort of zombie that has to eat brains in order to keep from going full zombie, as well as keeping her memories in tact. As a side effect, she also gains the memories of others from the brains she eats and ends up solving murders. 
