Though it could be easily forgotten in today's irony-loving world, the concept of the Teenage Mutant Ninja Turtles (TMNT) began as a joke. Creators Kevin Eastman and Peter Laird thought it would be pretty funny to fuse the legendary martial artist, Bruce Lee, with the least nimble animal they could think of: turtles. The end result were the Teenage Mutant Ninja Turtles, four vigilante heroes-in-a-half-shell trained by a sewer rat whose enemies included immortal samurais, ninja clans, other mutants, and an alien with a drooling brain for abs.

RELATED: Every TMNT Movie, Ranked According To Rotten Tomatoes

Whether they expected it or not, Eastman and Laird's creation became a cultural phenomenon following the popular '90s television show, which led to countless merchandise including toys, video games, movies, and comic books. These days, the franchise remains a hot commodity as its current ongoing comics series have found ways to renew interest in the classic characters. The turtles' comics continue to sell extremely well, especially these rare variants that have since become goldmines for hardcore collectors.

10 Tales of the Teenage Mutant Ninja Turtles #1 (1987)

Tales of the Teenage Mutant Ninja Turtles #1 Comic Book (1987)

Price By Grade: Low $7, Mid $18, High $60+ | Record Sale: $180

This issue marks the debut of the second comic book run of the TMNT but due to a printing error for issue #4 reprint from the first TMNT run, the cover artwork was mistakenly used earlier in the same month.

Consequently, this confused many readers, leading them to believe that this issue was a reprint. This caused sales to fluctuate despite normal circulation. Grabbing this issue is relatively easy for novice collectors as a near mint copy only costs under $200.

9 Teenage Mutant Ninja Turtles #4 (1987) - Print Error Variant

Teenage Mutant Ninja Turtles #4 comic print error variant

Price By Grade: Low $50, Mid $150, High $500+

As mentioned earlier, the cover art for this variant was intended for Tales of the Teenage Mutant Ninja Turtles #1. As a result, nearly 60,000 copies were recalled and destroyed, and approximately only 1,000 error copies remained in circulation, thus making this variant a pretty rare copy to come by.

The original cover art for issue #4 (published in 1985), shown on the right side of the image, is less rare and expensive but still highly collectible.

8 Teenage Mutant Ninja Turtles #7 Variant Reprint (1989)

Teenage Mutant Ninja Turtles #7 Variant Cover Reprint

Price By Grade: Low $12, Mid $30, High $115+

This blue wraparound issue features the head of an unnamed member of Krang's alien race, the Utroms. It's a variant of the original issue (cover shown on the left side of the image) which was first published in March 1986.

RELATED: 10 Best Teenage Mutant Ninja Turtles Crossovers

It was re-issued for a second-printing in January 1987 due to its popularity because it featured a monumental reveal that the mysterious ooze which created the Ninja Turtles and Master Splinter was originally created by the Utroms. In terms of TMNT lore, this is a classic twist where it's revealed that the villain was inadvertently responsible for creating the heroes who'd become a thorn on his side for years to come.

7 Tales of the TMNT #70 (2010)

Tales of the TMNT #70 comic book published in 2010

Price By Grade: Low $12, Mid $40, High $125+ | Record Sale: $280

This is the final issue of a six-year comic book series under Mirage Comics. At the end of its run, the comic was struggling to stand-out in a resurgent comic book industry, so only 1,062 copies were ordered for circulation.

It's a book that's valued mostly for its scarcity, which also concludes a successful run by writer Jake Black and renowned artist Jim Lawson who worked on TMNT comics for 20 years.

6 TMNT #29-#30 (2008-09)

TMNT #29, #30 limited 1,000 copies 2008-2009

Price By Grade: Low $55, Mid $180, High $300+

These series of issues are the scarcest of an underrated TMNT comic book, sporadically running for just 32 issues from 2001-2015. Due to the constant publishing difficulties the series faced at the latter part of its run, only 1,000 copies each of issues #29 and #30 were made for circulation. Moreover, issue #30 is the more coveted of the two since 300 copies had original sketches on the inside back cover.

The series ultimately ended its run with two final issues that were sold via online releases in 2014 and 2015, respectively, before finally printing them.

5 Teenage Mutant Ninja Turtles #100 Variant (2019)

Teenage Mutant Ninja Turtles #100 Peach Momoko Variant (2019) 250 copies

Price By Grade: Low $30, Mid $90, High $350+

This issue marked the 25-year anniversary of the TMNT's comic book debut, which was celebrated in December 2019 with various artists being commissioned to create variant cover artwork for the occasion.

Specifically, this variant cover by Peach Momoko only published 250 copies, which makes it an extremely rare and highly sought-after book by hardcore collectors because even if it it's a relatively new issue, it has high potential to increase in value over time.

4 Teenage Mutant Ninja Turtles #2 (1984)

Teenage Mutant Ninja Turtles #2 Comic Book 1984

Price By Grade: Low $8, Mid $30, High $125+ |  Record Sale: $3,200

The second issue printed in the TMNT series features the first appearance of April O'Neil, the reporter who eventually became an integral character in TMNT lore. She even temporarily becomes one of the female Ninja Turtles at some point in the comics.

RELATED: TMNT: 10 Things Fans Should Know About Venus, The Original Female Turtle

This issue also marks the first appearance of recurring TMNT supervillain Baxter Stockman, a mad scientist allied with Shredder and Krang who transforms into a half-human half-fly hybrid in the '90s TV series.

3 Teenage Mutant Ninja Turtles #3 (1985) - Color Error Variant

Teenage Mutant Ninja Turtles #3 1985 Comic Book Color Error Variant

Price By Grade: Low $125, Mid $310, High $1.2k+

This issue marks the first group appearance of the Utroms. Moreover, due to a printing error, approximately 500 copies had slight discoloration and a superimposed section that repeats the "Laird's Photo" sign, which is highlighted in the above image with a red border.

While a copy with the correctly printed cover (above, left) can be valued upward starting at $105 for a near mint copy, the error variant (above, right) is typically over a dozen times more valuable.

2 Teenage Mutant Ninja Turtles #1 (1984) 1st Print

Teenage Mutant Ninja Turtles #1 Comic Book 1984 1st & 2nd printing

Price By Grade: Low $1.2k, Mid $3k, High $12k+ | Record Sale: $88,000

The issue that started it all, especially a first-print copy, can be considered the holy grail of TMNT comic books. However, a high-quality copy of the book is typically hard to come by, so the more affordable second and third printings are sometimes more preferable. A second print could go from $300 to $3,600 while a third print racks up $50 to $1,000 at most.

One should be extremely meticulous in spotting slight differences, however, as some sellers tend to overvalue their copies (whether intentionally or not), believing their merchandise to be first-prints when in fact they're not. For example, the real deal (above, left) shows a distinctive crimson-red coloring compared to the second-print (above, right) which is closer to a shade of pink.

1 Turtlemania Special #1 Variant Gold Cover (1986)

Price By Grade: Low $515, Mid $1.8k, High $4k+ | Record Sale: $58,000

The regular cover (above, right) of this issue hovers around $400 in near mint condition, with a relatively scarce distribution of 3,000 copies in circulation. A high-quality silver cover variant can go for over $1,100, with only 100 copies made.

The gold cover (above, left), though, can be valued upward of thousands of dollars as there are only 10 copies in existence. This golden variant is without a doubt the rarest of all TMNT comic books.

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