Ankh

Ankh was created 800 years ago when ancient alchemists in the service of a powerful king attempted to raise their ruler to the level of godhood by creating fifty mystical artifacts called Core Medals (five sets of ten each), for him to use as weapons. Each was imbued with the abilities of a specific animal; more importantly, combining the power of three medals would allow the King to transform into Kamen Rider OOO, a superpowered being with access to these powers. Unexpectedly, however, the Core Medals eventually gained a sentience of their own, leading to the birth of five Greeed: artificial life forms comprised entirely of medals.

While originally aimless, with no driving purpose of their own, the Greeed gained full consciousness when a single Core Medal from each of the five sets was destroyed. More specifically, each of the Greeed began to feel a terrible void within themselves: a wish for completion that could never be truly fulfilled now that part of them was “missing”. Most of the Greeed began to attack human beings around them, absorbing their desires in an attempt to fill the void; Ankh, on the other hand, betrayed his fellow Greeed and allied himself with OOO instead. Though Ankh and OOO were able to subdue the remaining Greeed, Ankh was shortly betrayed himself as the king, overcome by the force of his own greed, lost control of his transformation. As the powers of the Core Medals ran wild, the king’s body was transformed into a stone coffin. Ankh (or rather, his right hand, which was the only part of him close enough to the coffin) was subsequently sealed away in this coffin with the other Greeed, where he lay dormant for eight centuries.

When the seal on the coffin is finally broken, Ankh is the first Greeed to awaken. Weak, disoriented, and only able to regenerate himself as a disembodied right arm, Ankh nevertheless manages to steal several Core Medals belonging to the other Greeed before making his escape. Eventually, however, Ankh is cornered by the servant of another Greeed and, backed into the corner, convinces a human bystander named Hino Eiji into using the Core Medals to transform into Kamen Rider OOO. From then on, Ankh works together with Eiji in an uneasy partnership: Ankh wants to regain his own Core Medals and avoid the wrath of the other Greeed, while Eiji wants to protect the people of the city from the Greeed's predations.

Eventually, Eiji and Ankh settle into a routine, moving together into the attic of Cous Coussier, the restaurant at which Eiji works part-time. Ankh also develops a sort of uncomfortable truce with the other characters orbiting around Eiji, including Hina, the body of the comatose police officer whose identity Ankh has assumed, and Chiyoko, the eccentric owner of Cous Coussier, who is convinced that Ankh is a poorly-socialized orphan from a foreign nation.

Over time, Ankh learns why he only regenerated as a right arm: the rest of him was split off when he was sealed inside the coffin, becoming an incomplete Greeed with its own separate consciousness. Eventually, this Ankh absorbs the original Ankh into himself in an attempt to reunify as a single Greeed. Before the original Ankh’s consciousness can be fully absorbed, however, Eiji destroys three of the second Ankh’s Core Medals, allowing the original Ankh to reassert control over his own body and become the dominant personality.

Unfortunately, for Ankh, this also means that he can never be a complete being (or as complete as a Greeed can ever be), as he'll never be able to amass all nine of his Core Medals. Subsequently, Ankh becomes fixated on obtaining all of the other Greeed’s Core Medals, in the hopes that this will somehow help him feel fulfilled. In the pursuit of this goal, Ankh abandons Eiji and allies himself with Maki, a Greeed that wants to destroy humanity (but is willing to hand all the medals over to Ankh in the process of doing so).

Now reintroduced back into the ranks of the other Greeed, Ankh becomes steadily more convinced that he despises his fellow Greeed even more than he resents humankind. His time spent among the human characters allows him to see clearly that to be a Greeed is to live an existence that is ultimately empty of meaning or fulfillment, eternally craving something that can never be attained; as a result, Ankh's desires themselves begin to change. Instead of longing to be ‘complete’, Ankh begins to focus on a wish to live, much in the way that humans are alive.

Meanwhile, with Ankh gone, Eiji has slowly begun the process of transforming into a Greeed, as he's convinced that this is the only way to defeat Maki. In the middle of a heated battle, Ankh tells Eiji that Eiji will never truly understand how terrible and empty it truly is to be a Greeed. In return, Eiji confesses that his one greatest wish, long forgotten even by Eiji himself, was to gain the power to protect the world -- a wish that Ankh inadvertently granted when he'd given Eiji the ability to transform into Kamen Rider OOO. Moreover, Eiji thanks Ankh wholeheartedly for this service.

Shocked, Ankh retreats in order to try and come to terms with the possibility that Eiji already considers Ankh alive. Or at least more than a glorified bag of magical quarters. Unfortunately, Ankh's moment of inattention winds end up being fatal, as Maki takes the opportunity to attack Ankh and damage the Core Medal that houses his consciousness. Nevertheless, Ankh returns to help Eiji in one last battle, allowing Eiji to use Ankh’s cracked Core Medal to battle Maki as Kamen Rider OOO.

After the battle, Ankh's medal breaks in half, but does not disappear entirely, leading Eiji to harbor hope that it may one day be restored. During the events of Mega Max, Ankh appears via a time distortion with a Kamen Rider from the future, more or less confirming that Eiji does in fact manage to eventually restore Ankh.