Titans (巨人 Kyojin?, lit. "Giant(s)") are a race of giant, man-eating humanoids that serve as the catalyst for the events in the series. The people inside the Walls were taught that they first appeared 107 years prior to year 850 and rapidly exterminated humanity to the point of near-extinction. In reality, they are transformed humans known as Subjects of Ymir and have existed for nearly 2,000 years.
Titans strongly resemble nude humans. They are typically bipedal with the limbs and features one would expect in humans; however, they are all deformed to some extent in body proportions (enlarged head, small limbs, etc.). Many Titans have exceptionally wide mouths with an array of square teeth. The vast majority of Titans have a masculine body shape, although all of them lack reproductive organs.
Unlike other species, Titans do not mate or interact with organisms other than humans; their sole purpose in life is to seek out and devour humans. They do not derive any real sustenance from humans either, as many of them did not taste human flesh for a century after the Walls were raised; but it did not affect their activity or decrease their numbers.
Some Titans do not react to pain, and all will move as long as there is sunlight. Titans do not possess a complete, functioning digestive tract; they merely have a stomach-like cavity that eventually fills up with what they swallow. After consuming a certain amount, they regurgitate the contents of the cavity before they continue eating more humans.
Most Titans show no signs of intelligence and act like mindless beasts—easy to trick, distract, and deceive. The Nine Titans are the exception: They have human level intellect due to being piloted by a human. However, some Abnormals are also able to sustain some of their former intelligence, such as Connie's mother and the Titan encountered by Ilse Langnar, both of which demonstrated the capacity to form thoughts and even communicate with humans.
Subjects of Ymir become Titans after being injected with Titan spinal fluid, triggering a near-instantaneous transformation. This is exploited by Marley after the Great Titan War, who turn undesirable Subjects of Ymir into Titans to use for war or at Paradis Island to roam aimlessly beyond the Walls. Titans oftentimes bear a strong resemblance to their original human bodies, though women who are turned into Titans lose most feminine body features.
Although the organic materials that make up the Titans' bodies appear to arise from nothing, they are said to be sent from invisible paths that transcend physical space. These paths connect all Subjects of Ymir to a single "Coordinate," the Founding Titan.
The Founding Titan can personally turn Subjects of Ymir into Titans. Karl Fritz created the Colossus Titans that make up the Walls this way. Due to his royal blood, Zeke Yeager can mimic this ability by screaming after administering his spinal fluid to his victims.
The body of Titans appears to violate several known laws of science, spontaneously generating both energy and mass. Their bodies are incredibly light, granting them human levels of maneuverability. Their extremely high level of activity and body temperature indicates the need for a massive intake of energy to fuel them, yet they apparently never need to eat at all, though most Titans kill their victims by appearing to do so. They possess and use vocal organs, but they do not need to breathe for survival.
Titans draw their primary source of energy from the sun, as they become inactive when deprived of sunlight. The absence of sunlight affects individual Titans differently: During experimentation, the captured Titan "Sonny" became docile and nearly comatose after only an hour's deprivation, while fellow captive "Bean" maintained a high level of activity three hours after last seeing sunlight. However, this only applies for the Pure Titans; the Nine Titans do not need sunlight to move, and neither do Titans controlled by either Zeke Yeager's Beast Titan or, presumably, the Founding Titan.
Titans possess incredible regenerative abilities. Although the capacity varies from Titan to Titan, all can regenerate lost body parts in a period of time ranging from seconds to minutes, even severed heads (unless the nape is severed with the head). One of the only sure-fire ways to kill them is by slicing an area one meter long and 10 centimeters wide on their nape. This is the location of the central nervous system of the Titan. In Pure Titans, it is only a spine of the human that was absorbed; but in the Nine Titans, it is an entire human body. Without a functioning nervous system to control it, the Titan dies. After death, Titan corpses rapidly evaporate to skeletal remains, then to nothing at all.
How Titans react to pain stimuli varies from one to another: Some Titans completely ignore agonizing injuries, even impalement through the heart, and attack nearby humans as normal. Others scream or writhe, seemingly in agony. Humans with the power of the Titans do not feel pain if their Titan forms are damaged.
Around 2,000 years ago, a slave named Ymir discovered a large tree while fleeing from her masters, the Eldians. The tree had an entrance that led to a pit full of water. Unaware of the water, Ymir entered the tree and immediately fell. As she sank, a mysterious, spine-like entity attached to her back; and she transformed into the very first Titan. With her new power, she returned to the Eldians and served under Fritz, eventually bearing him three daughters. When Ymir died, Fritz ordered his daughters to eat Ymir to retain her power, an action that split Ymir's power among her daughters. Eventually, it split into nine—the Nine Titans—which Eldia used to conquer Marley and establish the Eldian Empire.
However, after 1,700 years, Karl Fritz inherited the Founding Titan and chose to abandon the conflicts of the mainland. In his absence, the Great Titan War began; and the chaos it caused allowed the Marleyans to rebel and take over the continent. The King and many Eldians fled to Paradis Island, where he used Colossus Titans to construct three Walls around his territory. In the years after, Marley would send undesirable citizens to Paradis Island as Pure Titans, doomed to wander the island.
Types of Titans
Titans are classified according to their size and abilities. The following is a list of various known Titans so far.
Pure Titans (無垢の巨人 Muku no Kyojin?)
| Ranging from 2 - 15 m in height, these Titans compose the vast majority of observed Titans. They all resemble humans but with varying levels of deformity. Their only common feature is their mindless nature. They mindlessly attack nearby humans, making them easy to deceive. However, they are still dangerous due to their size, physical strength, and sheer numbers. They are often used as weapons of war, by Eldia in the past and Marley in the present.
Notable Titans of this type:
|Pure Titans that display abnormal behavior or intelligence are classed as Abnormal. Abnormals often ignore nearby humans and charge to more important locations where they can do more damage. The Colossus Titans found inside the Walls are unusually large, similar to the actual Colossus Titan, and have hardening abilities.
Notable Titans of this type:
The Nine Titans are fragments of Ymir's power. Humans who inherit them have the power of the Titans, which enables them to transform into their inherited Titan at will, gaining its special abilities while retaining their human body and intelligence. A human with the power of the Titans has access to advanced Titan abilities, such as focusing regeneration to specific parts of the body to increase the healing rate.
Titans of this type:
- Despite their English name originating from the Titans of Greek mythology, the Titans of Attack on Titan are much more influenced by the jötnar of Norse mythology. Most notably, both the Titans and the jötnar originated from an ancient being by the name of "Ymir."
- Some Titans are modeled after friends and acquaintances of Hajime Isayama. Sometimes, he will even take requests.
- While most Titans have a masculine appearance, a few of them possess feminine facial features, while still retaining their masculine body shape.
- Isayama revealed that his images of Titans were inspired by "Man-eating Mona Lisa" from Hell Teacher Nūbē series and dinosaurs from Jurassic Park series.