Ankh is one of the five Greeed, notable among his fellow homunculi for aiding Kamen Rider OOO though for his agenda. He is first introduced as the deuteragonist, before being a full-fledged antagonist and ultimately an anti-hero by the finale.
AppearanceAnkh appears as a hard-feathered bird Greeed, notable for having feathers that gradient from red to green. However upon losing Core Medals, he appears as a floating arm while retaining the feathery appearance. Upon possessing Shingo Izumi, Ankh takes the form of a blonde Shingo whose hair is parted in a rather unusual way for a normal human.
True to his nature as a Greeed, Ankh is extremely avaricious and full of an unquenchable thirst for possession that leads to consuming the world if unchecked. But like many of the Greeed, Ankh covets Core Medals, the source of a Greeed's power and existence. The need to gather the Core Medals through an ideal pawn in order to use the Core Medals is so he can evolve from a pile of coins into a living being.
Ankh, like the rest of the Greeed, was created 800 years ago through the Core Medals. Though he aided the original Kamen Rider OOO, a king who commissioned the Core Medals, Ankh was betrayed by the greedy king to complete his scheme to become a living god through the power of human desire. However, the power of the Core Medals overwhelmed the First OOO that turned him into a stone coffin that sealed the Greeed and Ankh's right forearm containing the Core Medal with his consciousness.
In 2010, Ankh manages to unseal himself and gather enough Cell Medals to recreate his forearm and remove the petrified OOO Driver that caused the release of the other Greeed. However, Ankh loses one of his Taka Medals when Eiji Hino takes it by accident. Though originally intending to force Eiji to return his medal, the appearance of Uva's Kamakiri Yummy forces Ankh to make Eiji the new Kamen Rider OOO and a pawn in his scheme to gather the Core Medals. Using the body of a mortally wounded detective named Shingo Izumi as a temporary vessel, thus keeping Shingo barely alive, Ankh planned to move undetected so he can gather enough Cell Medals to recreate his entire body with Eiji's help. However, when Eiji proves far more strong willed than he thought, Ankh is forced into promising him to give Eiji the OOO Driver so he could save lives rather than just to gather Cell Medals for Ankh.
Later, his reasons for the Core Medals revealed, Ankh finds that he cannot recreate his body even after reabsorbing his two Core Medals and only able to project a single rainbow-hued wing from his shoulder. Eventually, Ankh learns that the remaining his Core Medals reside within his original body which has developed into its own being bent on absorbing Ankh to be whole. After being absorbed by the other Ankh, Ankh regained his full powers by the time the Core Medal of the other self was destroyed. However, now unable to ever be truly complete and his Cell Medal-based body unstable, Ankh takes Shingo's body again and allies himself with Kiyoto Maki to become the receptacle of all the Core Medals in return to give the scientist the purple Core Medals to evolve into a Greeed himself. Counting on Eiji's new-found ability to destroy Core Medals, Ankh formulates a reckless plan to have OOO eliminate the other Greeed so he can use their Core Medals to convert Shingo's body into a Greeed form. However, seeing Ankh unworthy for his plans, Maki takes Ankh's Core Medals while critically damaging his Taka Medal housing his conscious mind. Not telling Eiji of his condition, Ankh helps him in their final battle with Maki by sacrificing himself so Eiji can finish off Maki's Kouryuu Greeed form as OOO Tajador Combo. As Maki dies and is sucked into the blackhole formed on his chest, the only Taka Medal housing Ankh's consciousness remained as its split into two with one half in Eiji's half as Ankh gives his final farewell to his friend. Finding the other half with Hina, Eiji vows to somehow restore his friend, traveling the world to find a way to do so.
In Kamen Rider × Kamen Rider Fourze & OOO: Movie War Mega Max, Eiji's hope of restoring his friend is strengthened when meet an Ankh from the future where the means of restoring his Taka Medal is possible. Though Ankh had to return to the future, Eiji knew they would meet again.