Regardless of which form he assumes, he also uses the Kougami Foundation's Medajaribur (メダジャリバー, Medajaribā) sword, which allows him to perform the OOO Bash (オーズバッシュ, Ōzu Basshu) finisher, and the Ride Vendor (ライドベンダー, Raido Bendā) motorcycle to combat the Greeed.
After aiding him in the fight, Ankh's spirit appears before Eiji to express gratitude to him and others for allowing the former to live and die as a human before giving him and Hina his broken Core Medal.
She also comes to realize that she relies on Eiji's desire to help to an unhealthy degree, takes steps to ensure he does not blindly sacrifice himself for other people's sake, and cares for Ankh as if he were her brother.
Shintaro Goto (後藤 慎太郎, Gotō Shintarō) is a former police officer who works for the Kougami Foundation to keep the world safe from the Greeed and eventually becomes Eiji's friend.
He initially traveled the world before returning to Japan, where he was hired by the Kougami Foundation to become the first user of the Kamen Rider Birth system with Shintaro Goto as his apprentice.
[6] The Greeed (グリード, Gurīdo)[c] are coin-based, animal-themed homunculi created by the First OOO via the power of 50 Core Medals as part of his plan to achieve godhood 800 years prior to the series.
As such, the Greeed became bent on consuming everything around them in a vain attempt at experiencing what humans normally take for granted, only to be sealed by the First OOO after he stole their Core Medals and was overwhelmed by their power.
When the seal is undone in the present, Ankh steals some of his fellow Greeed's Core Medals to handicap them due to his being unable to completely reform his body.
Uva (ウヴァ)[d] is an insect-themed Greeed and the most hot-headed of his kind who assumes the form of a young man wearing a green leather jacket to blend in with society.
As the Core Medal containing his consciousness survived, Uva possesses a man named Kusada and uses him to recreate his body before supporting Ankh in his fight against Kazari.
As a result, Uva is forcibly transformed into the Medal Vessel Chaos Form (メダルの器 暴走形態, Medaru no Utsuwa Bōsō Keitai), which Eiji eventually destroys.
Along the way, Kazari meets Kiyoto Maki and aligns himself with the scientist to find his missing Core Medals, diverting from the Greeed's original goal of consumption to evolution.
This new ideology leads to Kazari using Gamel, Mezool, and Uva as test subjects to experiment with the idea of a Greeed possessing foreign Core Medals.
His feline-themed Yummy are parasitic in nature, possessing the human and forcing them to partake in their desire even at the risk of their lives until they reach their complete form and consume the host.
Upon his awakening, he loses four Core Medals to an unknown party and takes on the form of a young man dressed in a grey mesh shirt over a black undershirt.
She comes off as the kindest member of her kind due in part to her methods being able to provide enough Cell Medals for all of them and serves as a mother figure as her desire is to know and feel true love.
Spurred on by Kiyoto Maki, she breaks off to achieve her desire by abducting several mother/child pairs and sealing them in her Yummy eggs to drain the love and life from them.
Their presence are mostly concealed until the Yummy eggs hatch into their complete forms and are compelled to return to Mezool and break up into many Cell Medals for her and the Greeed to ingest.
In addition, he believes desires are the purest and most powerful energy source in existence and that it plays a major role in the evolution of life on Earth.
An unnamed ancient king of a mysterious lost European civilization whose ball of desire (欲望の塊, yokubō no katamari) and god complex led to him becoming the First OOO (先代オーズ, Sendai Ōzu) 800 years ago.
Eventually, the king's avarice drove him to unite the Core Medals' power, only for them to overwhelm him and transform his body into a stone coffin that sealed four of the Greeed and Ankh's right arm for centuries.
Despite preferring to study the Greeed, Kiyoto is forced to work on the Kougami Foundation's Core and Cell Medal-related projects to fund his research.
They were eventually found and contained by the Kougami Foundation in the present due to their destructive power, but Kiyoto Maki steals them after severing his ties with the company.
Five of the Medals sense Eiji's lack of desire and infect him while Kiyoto absorbs the remaining five and eventually transforms into the series' version of the Kyouryu Greeed.
Matsudaira also performs the theme song for Kamen Rider OOO Wonderful: The Shogun and the 21 Core Medals alongside Shu Watanabe (as Eiji Hino) and Ryosuke Miura (as Ankh).
Believing that the world has changed little since his death, Gara takes the Core Medals back and gathers human desire to cause three time distortions in order to bring about a doomsday scenario.
After Eiji rescues Wakaba, Gara assumes his true Greeed-like Monster Form (怪人態, Kaijintai), only to be defeated by Kamen Riders OOO and Fourze.
Poseidon attempts to travel to another time period, only to be destroyed by Kamen Riders OOO and Aqua while his Core Medals end up in Lem Kannagi's possession.
Muchiri (ムチリ) is a man-made arthropod-themed Greeed with unlimited use of Core Energy that Foundation X scientist Professor Zeus created in an attempt to revive his colleague Aida and appears exclusively in the video game Kamen Rider: Memory of Heroez.
While Aida betrays Zeus to take control of Muchiri and achieve immortality, she is eventually defeated by Kamen Riders OOO, W, and Zero-One.