|What are you? A man? Or a Titan?|
|— Kitz Woermann to Eren Jaeger|
The power of the Titans (巨人の力 Kyojin no Chikara?) is the ability which allows for humans to transform into Titans. Unlike regular mindless Titans, those with the Power of the Titans are able to control their form and retain their human intelligence. It is often noted that these Titans are far more powerful than regular Titans and oftentimes display abilities unique to only them.
In order to transform, a human with the Titan ability must suffer an injury that draws blood (often self-harm) while having a solid goal or belief in mind at the moment of injury. However, being injured by another person is also sufficient. Once the transformation is initiated, a burst of energy is released (usually a bolt of yellow lightning or an explosion), followed by the generation of the Titan body and a release of hot steam. After transformation, the human body rests within the nape of the Titan's neck, the center of control. The human body is also merged with the Titan's flesh inside to varying extents, most frequently on the area of the cheeks below the eyes, rendering them immobile.
If a Titan form is pushed to its limit, the human will emerge from the nape of its neck, sometimes in a semi-conscious or entirely unconscious state. But if a Titan form is not exhausted, then its human form can emerge from the Titan form in full consciousness. In some cases, a human is able to partially emerge from their Titan body without fully leaving the nape.
After the Power of the Titans is used, oftentimes the area around the emerging human's eyes is marked by dark lines for a short time after. The amount of time the human possesses these marks appears to depend on how long, skilled, or overworked they used their Titan forms, ranging from several minutes to several hours.
In some cases, the ability to transform into a Titan is hindered by injuries inflicted on the human body. A human can transform into a Titan with injuries as severe as a missing limb, but only if a previous transformation has not occurred recently. If a human emerges from their Titan form and receives a severe injury, this person cannot transform into a Titan again until said injuries have fully healed.
Physiology and abilities
The average height among the transforming Titans is 15 meters, but this can vary greatly, ranging from the 5 meters of Ymir's Titan form to the 60 meters of the Colossal Titan.
Humans with the Power of the Titans also gain the Titan ability to regenerate and are capable of vastly improved healing abilities, even to the point of regaining lost limbs. However, regeneration from severe injuries, such as lost limbs, can strain their powers and prevent them from transforming for a period of time. It is evident that healing for a Titan's human form takes much longer than that of their Titan form. The time it takes to regenerate appears to depend on the extent of the injury and how focused the individual is on healing that area.
It is also shown that these Titans are not safe from regular Titans, and will be attacked even while transformed.
While not all Titan abilities have been identified, each inheritable Titan possesses a unique power. The Colossal Titan has been shown to possess significant control over his body, able to release devastating gusts of steam to ward off enemies or even completely evaporate his Titan form in seconds. The Armored Titan possesses hardened, armor-like skin covering all but the key areas of movement. The Female Titan is able to call upon mindless Titans with a scream, luring dozens towards her position with little time.
Annie's Female Titan has been shown to possess the ability to harden her skin to the point of near-indestructibility. She is able to selectively harden regions of her Titan body and even create a hard crystal around her human body, putting her in an apparently unconscious state with no need for nutrient intake. It seems, however, that not all transformed Titans possess this hardening ability.
The first Titan to appear chronologically within the series, the Colossal Titan is of 60 m class. This grants him incredible strength like no other, capable of causing monumental destruction with little effort or damage sustained on his body. Due to this size, its body temperature is extremely high to the point that it is constantly emitting steam. However, because this he is so large, the Colossal Titan can only move slowly while in its form.
It is the largest Titan form seen so far in the series, and four times the height of the regular Titans of the tallest class (15 m). Strong enough to break down the Walls surrounding humankind with a single and very hard-focused kick. It has a unique ability to "superheat" its body to produce incredibly hot steam as a defense. The heat of this steam is so intense that it is able to keep dozens of experienced soldiers at bay.
The Armored Titan is capable of transforming himself into a 15 m class Titan. This Titan possess hardened plates of skin all over his body which serve as armor.
This type of Titan is well-built and has a hunched profile. Its only visible weaknesses are the small areas on the backs of its joints where there is no armor. Though not particularly fast, this form is strong and agile, capable of destroying a fortified Wall after a sufficient running start.
Eren Jeager is the first human with the Power of the Titans to be revealed in the series, his Titan being a 15 m class. Its most prominent characteristics are its elongated ears, fleshless jaws and highly muscular build.
Eren's Titan form has so far been shown to have fairly substantial physical strength, knowledge of martial arts techniques, and incredible endurance. Prolonged and repeated use of this Titan form has allowed Eren to gradually increase control over its initially unstable mental state. Its eyes are a piercing gray in the manga, and emerald-green in the anime; wherein they are often seen to be glowing bright green.
Annie Leonhart can transform into a 14 m class Titan with a distinctively feminine build and short, blonde hair. Her transformation endows her with immense strength and speed.
A Titan of athletic appearance with lean muscle and minimal skin, the Female Titan is a Titan of unusual power and intellect. It has the stamina and focus to maintain a running pace capable of keeping up with horses over a long distance; as well as the intelligence to defend itself from multiple omni-directional mobility gear attacks by prediction of the device's movements. This Titan form also has the unique ability to harden its body parts by generating a crystalline substance across chosen areas of its body; allowing it to simultaneously protect its nape and fight. Combined with refined martial arts techniques, it can perform incredibly deadly and destructive attacks. When cornered, the Female Titan's call has the ability to draw other Titans to it and drive them into a feeding frenzy.
Ymir's Titan is a 5 m class Titan with long, black hair, very large irises and an agile, chimpanzee-like body. This form grants Ymir rather long arms and sharp claws. It provides her with such great agility that her Titan appears to be "dancing".
The smallest Titan form known yet, this Titan form has a mouth with all pointed teeth, as well as sharp claws that can either be used to grasp on to things or for combat. Its long arms and small, muscular body enables it to maneuver itself around with great speed and agility in the same environments as those with omni-directional mobility gear, making it a formidable foe in battle.
The Beast Titan is an extremely unusual specimen, having a distinct, ape-like appearance. Its body structure and facial features are like that of a human's and it walks upright like one as well. It stands at a previously unseen 17 meters in height. Dark fur covers the large majority of its body, with the exception of its face, hands, feet, and torso. Its arms are also elongated, with long fingers and fully-functional thumbs. The proportions of Its upper body are similar to those of the Colossal Titan, possessing a massive chest and small head, as well as disproportionately long arms.
- Many transformed Titan forms are modeled after mixed martial artists. For instance, the Armored Titan is modeled after Brock Lesnar and Eren's Titan is modeled after Yūshin Okami.