Fans have long speculated that the Teenage Mutant Ninja Turtles represent the four elements/four humors, which also compose the major ingredients of certain personality types. Now, this theory has just been confirmed in Teenage Mutant Ninja Turtles #132, and it may also go a long way to explaining the enduring popularity of the franchise.

In the current run of IDW’s Teenage Mutant Ninja Turtles, the four brothers and their ally Jennika find themselves training under Oroku Saki aka the Shredder. Their former arch-enemy turned mentor is taking the five Turtles deeper into their training than Master Splinter ever did. Not only is he forcing them to face their greatest fears and regrets, but he is also teaching them to harness ancient and mystical powers. During this training process Shredder takes his pupils to a thin place, a sort of mystical sub-dimension that does not occupy normal space. This particular one is an entrance to the spirit world and is populated by magic, strange vegetation, crystals, and bird-shaped spirits. Here they are instructed to each make a gofu, a talisman-like object that is also known as an ofuda in Japanese Shinto and Buddhism, and are created from different materials. The Turtles use twigs, mud, crystals, plants, and even animal bones to construct their gofus, all of which they shape into patterns that reflect their true inner selves.

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In Teenage Mutant Ninja Turtles #132, by Sophie Campbell and Ronda Pattison, the Turtles' elemental talismans are connected to the five elements of the Chinese Wuxing philosophy. Each gofu gives the Turtles new powers, tethers them to the spirit world, and allows them to sense one another. The five elements are fire, water, wood, metal, and earth, and each plays off the other, generating one another, and having both opposing and complementary effects. None of them can exist alone, and they are all more powerful together, just like the Ninja Turtles.

It is never explicitly stated in the comics which Turtle matches up with each element, but fans have made many guesses over the years. Leonardo is often associate with water, because he is calm and able to find a path through any difficult situation. Raphael is associated with fire because he’s hotheaded and powerful, but also has surprising warmth for his brothers and friends. Michelangelo is associated with earth, because he is hardheaded and often takes longer to learn lessons, but is also the most grounded. Donatello usually seen as metal or wind, as both substances can be both powerful weapons or useful tools for advancing knowledge. That leaves Jennika as wood, or heart. It is associated with strength, flexibility, hope, and the transformation of seasons, just as she was transformed into a Turtle. Though these specific relationships are just fan conjecture, they also help explain the continuing popularity of TMNT.

Turtles Discover their Gofu (3)

Whether you are talking about four or five elements, each has a distinctive link to a different personality type, all of which are embodied by the ninja brothers. Leadership, intellectualism, anger, and being a party-dude are four personality types that would seem almost opposed to one another, but work within the Turtles' dynamic. Much like the idea of the Chinese elements, they play off one another, and with the differences in personalities every fan can find at least a little of themselves in one of the turtles.

Much like natural elements, the Turtles are often in conflict with one another, but it has been shown that the brothers need each other to be complete. The fan theory of associating the Teenage Mutant Ninja Turtles with those elements has now been confirmed, and it's an important step to seeing why the franchise works so well, and understanding the enduring popularity and power of the Heroes in a Half Shell.