In 1964, Hasbro successfully broke into the gigantic doll market with an entry designed for boys. Its innovation was as simple as calling the dolls "action figures." Their G.I. Joe line was a massive success. However, by the end of the 1970s, the costs of producing the over-sized figures were becoming cost-prohibitive, so the line was in trouble. Luckily, a rival toy company, Kenner, came up with a clever solution to the problem. In the late 1970s, Kenner obliterated the competition with the release of its line of Star Wars action figures to tie in with the then-new film. Kenner was so taken aback by how popular the film was, they didn't even have the toys ready in time for Christmas 1977, so they had to sell pre-orders instead.

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Hasbro took that idea and used it on its G.I. Joe line, creating a whole universe where the heroic military figures fight against villainous terrorists. Hasbro's innovation was to make its toys highly articulated, so you could do a lot more with the figures than the Star Wars equivalents. G.I. Joe became a cultural sensation, with a hit toy line, cartoon and comic book series. Here, according to ToyWorth, are the 15 most expensive G.I. Joe action figures. These are all figures that were released individually and in stores. No mailaways or prototypes or special two-packs. Prices are based on figures sealed in original packaging.

15 FLINT ($375)

One of the interesting aspects of the G.I. Joe line of toys is that the ongoing cartoon series that tied into the toy line did not debut until 1985. Therefore, the characters of the fourth series of G.I. Joe toys, released that same year, became the main faces of the new TV series. As a result, it was characters like Flint who became household names, while most of the original members of the team faded into history.

As part of the fourth series, Flint was one of the first G.I. Joe figures that came with a unique neck joint that was a ball, allowing the character to look up, down and left and right. It is impressive that Hasbro kept trying to improve the figures even as the line was selling like crazy.

14 DUSTY ($400)

Besides being one of the more popular characters on the G.I. Joe TV series, the Dusty figure was a very popular one back in the day, likely because of the unique way that designers worked actual felt into his "dust helmet" that he uses as a desert soldier. One of the most amusing things about the G.I. Joe squad was how specialized some of these characters were and yet they all went on the same adventures together.

A soldier who knows how to handle himself in the desert is very useful, but he is a bit less useful outside of that environment. Dusty's real name, Ronald Tadur, was based on Ronald Rudat, the popular Hasbro artist who designed most of the early G.I. Joe figures (on the cartoon series, Dusty's last name became Rudat).

13 BARONESS ($450)

One of the hardest things to do with a toy line geared towards young boys is to develop female figures, as the very same gender politics at work in pushing the idea of a toy "for boys" naturally leads to the idea that a "girl" toy in said line of toys "for boys" would not be desirable. And sure enough, the Baroness toy was not particularly popular at the time. That, though, likely helped its collectability years later.

In general, the Baroness was a good role overall. There weren't many female villains given as much of a personality as the Baroness was back in the day. The comic book tends to treat her better than the animated series, but even in the cartoon she comes off pretty well compared to other characters.

12 ZAP (TWO-HANDED BAZOOKA) ($500)

As noted, we're not going into this to spotlight rare prototypes. This list is for toys that you literally could have just gotten on the shelf if you wanted to buy a G.I. Joe figure in 1982 or whenever. However, with that in mind, when there are variations on a figure that was released to the public, we'll count it, if it makes the figure valuable.

That's what happened with Zap, the Joe squad's bazooka soldier. On the drawing that comes with the figure, it shows Zap firing a bazooka that has two handles, so unsurprisingly, the bazooka was originally released with two handles. However, the second handle kept breaking the the thumb off of the figure, so Hasbro eventually fixed it and released a single-handled bazooka that wouldn't break off the thumb, but naturally, those original versions are very rare and thus, more valuable.

11 DESTRO ($500)

There are so many things about Destro that make him such a fascinating character. First off all, there's the notion that he is not exactly an active enemy combatant, which allows Destro to attempt to portray himself as above the fray. This ties into his second notable trait, that he is a member of Scottish royalty. He tries to act like that makes him better than the other members of Cobra, and sometimes, he does act more noble, but in general he's just as bad as the others.

Finally, though, there's the most notable Destro trait - that freakin' awesome looking metal mask that he wears! The shiny metal head (which was designed to evoke the Man in the Iron Mask) made the Destro figure a must-have at the time (and today).

10 SHORT-FUZE (CLOSED MORTAR HANDLE) ($600)

One of the major concerns with the G.I. Joe line of toys was maintaining the "Kung Fu grip" that the toys had become famous for back in the days when they were using strong rubber hands to make them grip things easier. The rubber, of course, then fell apart and the grip was useless. What's even more hilarious is how the term has no meaning -- there is no connection to Kung Fu at all.

The 1980s toys used plastic with a little give, allowing them to expand enough to let an object into their hands, but strong enough to grip it. Thus, their big problem was when toys would spread the grip too far off and break the toy. That was an issue with the closed mortar handle for Zap, so they added an easier-to-grip open handle. The original closed grip mortar with Zap are rarer and more valuable.

9 STORM SHADOW ($600)

The way that the G.I. Joe system used to work in the old days was that Hasbro would design the figures and then they would give them to Larry Hama, the writer of the G.I. Joe comic book series for Marvel, the creatives of which would then help Hasbro come up with the overall G.I. Joe vs. Cobra plotline for the toy series.

Hama would then come up with a background and a personality for the character, and often a real name. Hasbro came up with the codenames (and occasionally the real ones, too). Storm Shadow, released in 1984 as part of series 3, was the first Asian character released in the series, and Hama didn't like that the first Asian character was a villain, so he slowly turned Storm Shadow into a good guy.

8 SCARLETT (VERSION TWO) ($625)

An impressive aspect of the G.I. Joe toy line by Hasbro is that they were constantly working to improve the figures. Sometimes, when they would come up with a particularly notable improvement, they couldn't keep themselves from wanting to use it as much as possible. This is what led to the famous "series 1.5" figures of 1983.

You see, in the original G.I. Joe figures, the arms of the figures did not bend. That naturally limited the amount of articulation that kids could do with the figures, so Hasbro worked out new arms and legs that could bend at the knees and elbows and re-released the entire first series again with the new arms and legs. So, while this is not technically another edition of Scarlett, it is a different version, since the arms bend.

7 FIREFLY ($650)

The collectibility of Firefly is an interesting one, since he was not a particularly early figure release -- he came out in the third series -- nor was he all that prominently featured on the cartoon series or the comic book series. He did get a bit more attention in the comic book than the cartoon, though.

No, Firefly is just one of those rare examples of a toy becoming really popular because of how cool he looked. The Cobra saboteur's design was striking, with a sort of mixture between a ninja and a commando and he became a huge hit with fans. As a result, the demand on the figure has been strong enough that it is one of the most valuable ones in existence.

6 SNAKE-EYES (FOURTH SERIES) ($650)

In the history of the G.I. Joe toy line, there were two figures that were so popular, they had to constantly make new editions. One was Sgt. Slaughter and the other was Snake-Eyes. As a result of there being so many Snake-Eyes and Sgt. Slaughters made, you would think that it would depress the value of the figures a bit. Interestingly, for Slaughter, that's certainly been the case (plus, of course, the character's popularity hasn't exactly held up in the ensuing years).

With Snake-Eyes, though, the second revamp for Snake-Eyes (released as part of the fourth G.I. Joe series in 1985) also came with the inclusion of Timber, Snake-Eyes' pet wolf! That helped to make this release such a unique one, since it has more than held its value over the years.

5 DUKE ($700)

Duke was originally not offered as an individual figure. He was just a mail-order figure with the second series in 1983. However, the character was so popular that he was then released individually as part of the third series release in 1984. Duke's high ranking on this list is clearly an example of a character's popularity driving the value.

Duke was introduced in 1983, which is when the first cartoon miniseries debuted, and thus, Duke got a huge boost by being shown as the leader of the team in that first miniseries. This was despite the Joe figures coming with a leader figure when they debuted in Hawk! The cartoon, though, was the most popular way that people got to know the Joes, so Duke was locked in as the leader.

4 SCARLETT (FIRST SERIES) ($700)

Looking back, you really have to give Hasbro some credit for launching the G.I. Joe toy line with such a progressive lineup (for the time) of having both a woman and an African-American soldier (Stalker) on the original team. Of course, the downside of that from a sales perspective is the problem that we mentioned earlier with Baroness, which is that when you are specifically targeting boys with your toy line, it is hard to then sell them a "girl" toy.

As a result, Scarlett, despite being featured so prominently on the G.I. Joe cartoon series and the comic book, was not a particularly strong-selling toy. Amusingly, she had different love interests in both series. In the cartoon, she was with Duke while in the comics, she was with Snake-Eyes. But we digress. The strength of the character's appeal, or lack thereof in the past, directly led to the toy being more valuable today, since she's harder to find!

3 COBRA COMMANDER ($900)

The main villain of the G.I. Joe series was Cobra Commander, who, naturally enough, commanded the terrorist group known as Cobra. The character was a charmingly vicious bad guy and he was in great demand as a toy at the time. Initially, he was available only as a mail-in figure.

In fact, throughout the first few series, Cobra Commander continued to be just a mail order figure. However, remember when we noted how Hasbro went back and added bendable arms to all of their figures? Well, when the company did that with all the original figures, it also did so with Cobra Commander and then briefly offered him up for individual release. The relative rarity of this figure's release led to it being one of the very most valuable G.I. Joe toys.

2 SNAKE-EYES (VERSION TWO) ($1050)

One of the most amusing aspects of Snake-Eyes' design is that one of the most popular toy designs of all-time was done simply to save money. You see, with the rest of the G.I. Joe team, they would be produced in little pieces of plastic that would then be painted to match the figure that they were going with, so a whole lot of green paint was involved.

With Snake-Eyes, however, they could just produce black pieces of plastic and then, voila, no paint required! Snake-Eyes was already finished as soon as he was produced! Of course, a dude dressed all in black turned out to be very popular with fans, so it worked out well. This version of Snake-Eyes is the first one with bendable arms.

1 SNAKE-EYES (FIRST SERIES) ($1300)

When you look back on the original G.I. Joe team, it is easy to see why writer Larry Hama was drawn to the characters that he ended up writing the most. You had a bunch of nondescript looking white guys and then you had a black guy, a woman, a guy named "Rock and Roll" with a big blond beard and a cool-looking ninja. Hama soon built almost all of his stories around those four characters.

As the series continued, there was no escaping how unique Snake-Eyes was, both in his design but also in how Hama wrote him as a scarred veteran who learned the ways of the ninja. He is one of the most influential characters of the 1980s -- Deadpool's look was partially inspired by Snake-Eyes -- and it is no surprise that the first edition of Snake-Eyes' action figure is the most valuable G.I. Joe figure.

What's the most expensive G.I. Joe figure you ever owned? Let us know in the comments section!