List of Kamen Rider OOO characters

Eiji Hino (火野 映司, Hino Eiji) is a politician's son who grew up in a lavish environment. But his life was changed while Africa when he attempt to use his fortune to help out a small village only funded a civil war that cost the life of a little girl he befriended, causing him to renounce his lifestyle and become a wandering vagabond willing to help those in need. Returning to Japan to allegedly fund more of his world travels, Eiji's latest part-time job at the Kougami Art Museum resulted in him getting unwittingly entangled in the chain of events that occurred after the Greeed were released when Ankh gives the ability to become Kamen Rider OOO to fight them. Eiji agrees to help Ankh in gathering Cell Medals on the condition of using his power to save lives, later allying himself with the Kougami Foundation while learning more of the Greed.

Eiji's lack of selfish desires would he become troublesome when became a host to half of the purple Core Medal set, attempting to keep himself from going berserk and transform into a Greeed. Soon after, Eiji learns from Kousei Kougami that the only way to counteract the purple Core Medals is to acquire a desire of his own. Eiji remembers that his desire is to have power to help others, agreeing to absorb all of the Cell Medals in the Kougami Foundation's possession to achieve that desire as he used them all in an attempt to destroy Maki in one attack. Ultimately, a dying Ankh gives Eiji his Core Medals to maintain himself to defeat Maki while losing all the Core Medals but the broken Hawk Core Medal containing Ankh's mind in the process. After realizing the power that he seeks are those he had bonded with, he resumes his world traveling with Ankh's spirit following him.

In Movie War Mega Max, revealed to be working with the Kougami Foundation to create new Core Medals in hope of restoring Ankh's Core Medal, Eiji is helped by a future version of Ankh who gives him Core Medals along with the Super TaToBa Medals. Both Movie War Ultimatum and Super Hero Taisen reveal Eiji acquired the restored orange and purple Core Medals, the latter movie having him give the Gokaigers one Core Medal from his six usual sets that they use to create Ranger Keys to each assume an OOO Combo form.

As OOO, Eiji inserts three Core Medals into the OOO Driver (オーズドライバー, Ōzu Doraibā) belt and activates the transformation with the O Scanner (オースキャナー, Ōsukyanā) with use of the Medajaribur (メダジャリバー, Medajaribā) sword and Ride Vendor (ライドベンダー, Raidobendā) motorcycle provided by the Kogami Foundation. The Core Medals (コアメダル, Koa Medaru) are products of alchemy created 800 years ago by the King's alchemist to create artificial life, drawing from characteristics of different animals, forming the core of the Greeed. Each Core Medal set is color-coded with Eiji using an entire set to assume a Combo (コンボ, Konbo) form or mix and match with other Core Medals to create other forms, the animal emblems appearing on the three-sectioned O Lung breastplate.

• Tatoba Combo (タトバコンボ, Tatoba Konbo) is OOO's main combination, using the powers of the Hawk (タカ, Taka), Tiger (トラ, Tora), and Grasshopper (バッタ, Batta) Core Medals. OOO uses the Hawk Head (タカヘッド, Taka Heddo) to gain powerful sight and accuracy to pinpoint a specific Core Medal with a Greed's body, the Tiger Arms (トラアーム, Tora Āmu) arms him with the Tiger Claw (トラクロー, Tora Kurō) gauntlets, and Grasshopper Legs (バッタレッグ, Batta Reggu) allow OOO to jump and kick with great strength. This Combo's Scanning Charge finisher is a Rider Kick called the Tatoba Kick (タトバキック, Tatoba Kikku), where after jumping high up with the power of the Grasshopper Legs, Kamen Rider OOO descends with a drop kick through the three rings that form, surrounding him with a different aura based on the Hawk, Tiger, and Grasshopper Medals. Two variations of the form are "Tatoba Combo (Purple Eye)" (タトバコンボ（パープルアイ）, Tatoba Konbo (Pāpuru Ai)) while under the Purple Core Medals' influence and "the True OOO" (真のオーズ, Shin no Ōzu) when he absorbed all the Cell Medals possessed by the Kougami Foundation. The Tatoba Combo is lost when all the Core Medals are sucked into the black hole created by the destruction of Dr. Maki, but is recovered during the events of Kamen Rider × Kamen Rider Fourze & OOO: Movie War Mega Max when Ankh steals a set of the Medals from Kamen Rider Poseidon.
• Gatakiriba Combo (ガタキリバコンボ, Gatakiriba Konbo), also known as the "Strongest Combo" (最強コンボ, Saikyō Konbo), is Kamen Rider OOO's green combination, using the powers of Uva's Core Medals: the Stag beetle (クワガタ, Kuwagata), Mantis (カマキリ, Kamakiri), and Grasshopper Core Medals. OOO uses the Stag Beetle Head (クワガタヘッド, Kuwagata Heddo) to generate lightning, while the Mantis Arms (カマキリアーム, Kamakiri Āmu) arm him with the Mantis Sword (カマキリソード, Kamakiri Sōdo) armblades. When both are used with the Grasshopper Legs, OOO's Gatakiriba Combo allows him to use the Branch Shade (ブレンチシェイド, Burenchi Sheido) ability to clone himself for his Gatakiriba Kick (ガタキリバキック, Gatakiriba Kikku) Scannining Charge or to have the clones assume OOO's other Combo forms.
• Latorartar Combo (ラトラーターコンボ, Ratorātā Konbo), also known as the "Scorching Combo" (灼熱コンボ, Shakunetsu Konbo), is Kamen Rider OOO's yellow combination, using the powers of Kazari's Core Medals: the Lion (ライオン, Raion), Tiger, and Cheetah (チーター, Chītā) Core Medals. OOO uses the Lion Head (ライオンヘッド, Raion Heddo) to generate bright flashes, while the Cheetah Legs (チーターレッグ, Chītā Reggu) allow him to move at blurring speeds while delivering multiple kicks. When both are used with the Tiger Arms, OOO's Latorartar Combo allows him to use the Liodias (ライオディアス, Raiodiasu) ability to generate an aura of heat. His attacks include Revol Spin Kick (リボルスピンキック, Riboru Supin Kikku) and the Gush Cross (ガッシュクロス, Gasshu Kurosu) Scanning Charge.
• Sagohzo Combo (サゴーゾコンボ, Sagōzo Konbo), also known as the "Gravity Combo" (重力コンボ, Jūryoku Konbo), is Kamen Rider OOO's gray combination, using the powers of Gamel's Core Medals: the Rhino (サイ, Sai), Gorilla (ゴリラ, Gorira), and Elephant (ゾウ, Zou) Medals. On their own, the Rhino Head (サイヘッド, Sai Heddo) enables strong head-butting attacks, the Gorilla Arms (ゴリラアーム, Gorira Āmu) provide the Gori Bagōn (ゴリバゴーン, Gori Bagōn) gauntlets, and the Elephant Legs (ゾウレッグ, Zou Reggu) produces stomp tremors. When all three are used in Sagohgzo Combo, OOO gains superhuman strength and gravity manipulation. His attacks include the Bagōn Pressure (バゴーンプレッシャー, Bagōn Puresshā) rocket punch, the Zuō Stomp (ズオーストンプ, Zuō Sutonpu) drop kick, and the Sagohzo Impact (サゴーゾインパクト, Sagōzo Inpakuto) Scanning Charge.
• Tajadol Combo (タジャドルコンボ, Tajadoru Konbo), also known as the "Blazing Combo" (炎のコンボ, Honō no Konbo), is Kamen Rider OOO's red combination, using the powers of Ankh's Core Medals: the Hawk, Peacock (クジャク, Kujaku), and Condor (コンドル, Kondoru, named "Condol" on merchandise) Core Medals. OOO uses the Peacock Arms (クジャクアーム, Kujaku Āmu) to arm himself with the shield-like Taja Spinner (タジャスピナー, Taja Supinā) gauntlet for Giga Scan (ギガスキャン, Giga Sukyan) attacks, while the Condor Legs (コンドルレッグ, Kondoru Reggu) equip him with the talon-like Raptor Edge (ラプトルエッジ, Raputoru Ejji) attachments that enhance his kicks. When both are used with the enhanced Hawk Head Brave (タカヘッド・ブレイブ, Taka Heddo Bureibu), his O Lung emblem resembling a phoenix, OOO Tajadol Combo uses winged projections called the Peacock Wings (クジャクウイング, Kujaku Uingu) while able to fly. This Combo's Scanning Charge finisher is a Rider Kick called the Prominence Drop (プロミネンスドロップ, Purominensu Doroppu).
• Shauta Combo (シャウタコンボ, Shauta Konbo), also known as the "Marine Combo" (海のコンボ, Umi no Konbo), is Kamen Rider OOO's blue combination, using the powers of Mezool's Core Medals: the Orca (シャチ, Shachi), Electric Eel (電気ウナギ, Denki Unagi), and Octopus (タコ, Tako) Core Medals. On their own, the Orca Head (シャチヘッド, Shachi Heddo) enable OOO to use sonic waves, spray jets of water, and dive underwater for up to 3 hours, the Electric Eel Arms (電気ウナギアーム, Denki Unagi Āmu) uses the Electric Eel Whips (電気ウナギウィップ, Denki Unagi Wippu) that are stored in the Eel Shoulders (ウナギショルダー, Unagi Shorudā), and the Octopus Legs (タコレッグ, Tako Reggu) allow OOO in both attaching to any surface while splitting up into tentacles that can trap a target or barrage a target with kicks. When all three are used in Shauta Combo, OOO gains the ability to liquefy his body while excelling in underwater combat. His attacks include the Voltarm Whip (ボルタームウィップ, Borutāmu Wippu) and the Octo Banish (オクトバニッシュ, Okuto Banisshu) Scanning Charge.
• Putotyra Combo (プトティラコンボ, Putotira Konbo), also known as the "Invincible Combo" (無敵のコンボ, Muteki no Konbo), is Kamen Rider OOO's purple combination using the powers of the Ptera (プテラ, Putera), Tricera (トリケラ, Torikera), and Tyranno (ティラノ, Tirano) Core Medals. OOO uses the Ptera Head (プテラヘッド, Putera Heddo) to equip himself with the wing-like External Fin (エクスターナルフィン, Ekusutānaru Fin) attachments for either flying or generating freezing winds, the Tricera Arms (トリケラアーム, Torikera Āmu) uses the extending Wind Stingers (ワインドスティンガー, Waindo Sutingā) blades mounted on the Tricera Shoulders (トリケラショルダー, Torikera Shorudā) to impale targets, and the Tyranno Legs (ティラノレッグ, Tirano Reggu) uses the Tail Divider (テイルディバイダー, Teiru Dibaidā) tail and Legsteranail (レグステラネイル, Regusuteraneiru) foot claws. Initially rendering Eiji a berserker while gradually turning into a Greeed, arming him with the Medagabryu (メダガブリュー, Medagaburyū), Putotyra Combo enables OOO to destroy the other Core Medal types. This Combo's Scanning Charge finisher is the Blasting Freezer (ブラスティングフリーザ, Burasutingu Furīzā), restraining the target before freezing them to shatter, his Putotyranno Hissatsu (プトティラノヒッサツ, Putotira no Hissatsu) attacks with the Medagabryu being Axe Mode (アックスモード, Akkusu Mōdo)'s Grand Of Rage (グランド・オブ・レイジ, Gurando obu Reiji) and Bazooka Mode (バズーカモード, Bazūka Mōdo)'s Strain Doom (ストレインドゥーム, Sutorein Dūmu).
• Burakawani Combo (ブラカワニコンボ, Burakawani Konbo) is Kamen Rider OOO's orange reptilian Combo form that first appeared in Kamen Rider OOO Wonderful: The Shogun and the 21 Core Medals. It uses the powers of the Cobra (コブラ, Kobura), Turtle (カメ, Kame), and Crocodile (ワニ, Wani) Core Medals that Eiji acquired from Tokugawa Yoshimune when Gara's time distortion brought him and his friends to Edo. OOO uses the Cobra Head (コブラヘッド, Kobura Heddo) to double his eyesight and add infrared perception that can even see in absolute darkness, Turtle Arms (カメアーム, Kame Āmu) arming him with the Goura Guardner (ゴウラガードナー, Goura Gādonā) which form the Gora Shielduo (ゴーラシールデュオ, Gōra Shīruduo) energy shield, and the Crocodile Legs (ワニレッグ, Wani Reggu) with sharp saw-like attachments known as the Saw Deadscythers (ソウデッドサイザー, Sō Deddosaizā). When all three are used in Burakawani Combo, OOO heals him with the Soma Venom (ソーマ・ヴェノム, Sōma Venomu) and uses the Burahngi (ブラーンギー, Burāngī) pungi to summon a giant cobra from the back of his head for his Cappello Brush (カぺロブラッシュ, Kapero Burasshu) attack. His Scanning Charge is the Warning Ride (ワーニングライド, Wāningu Raido) slide kick attack. While Burakawani Combo was lost when the Core Medals dissolve after the defeat of Gara Dragon, Eiji regains the ability in Kamen Rider × Kamen Rider Wizard & Fourze: Movie War Ultimatum with recreated orange Core Medals.
• Super Tatoba Combo (スーパータトバコンボ, Sūpā Tatoba Konbo) is the evolved form of Tatoba Combo that first appeared inKamen Rider × Kamen Rider Fourze & OOO: Movie War Mega Max. It uses three Core Medals that were created in the future: The Super Hawk (スーパータカ, Sūpā Taka) Core Medal that provides the Super Hawk Head (スーパータカヘッド, Sūpā Taka Heddo), Super Tiger (スーパートラ, Sūpā Tora) Core Medal that provides the Super Tiger Arms (スーパートラアーム, Sūpā Tora Āmu) with enhanced Tiger Claw Solid (トラクローソリッド, Tora Kurō Soriddo) gauntlets, and the Super Grasshopper (スーパーバッタ, Sūpā Batta) Core Medal that provides the spiked Super Grasshopper Legs (スーパーバッタ, Supā Batta Reggu). Because the Super Core Medals have "surpassed time", they give OOO the ability to temporarily stop time; Eiji uses this to fight Rem Kannagi, who also possesses future Core Medals, on an equal footing. This Combo's Scanning Charge finisher is a Rider Kick called the Super Tatoba Kick (スーパータトバキック, Sūpā Tatoba Kikku), an enhanced version of the Tatoba Kick.
• Mukachiri Combo (ムカチリコンボ, Mukachiri Konbo) is a poisonous bug-themed combo form of OOO in a video game Kamen Rider: Memory of Heroez. It uses three poisonous bug-themed Core Medals: The purple colored Centipede (ムカデ, Mukade) Core Medal that provides the Centipede Head (ムカデヘッド, Mukade Heddo), the yellow colored Bee (バチ, Bachi) Core Medal that provides Bee Arms (バチアーム, Bachi Āmu) (a shield on its left wrist and a stinger on its right wrist), and the silver colored Ant (アリ, Ari) Core Medal that provides the Ant Legs (アリバッタ, Ari Reggu). In this Combo form, it allows OOO to be immune to any poisons. His Scanning Charge is Mukachiri Kick (ムカチリキック, Mukachiri Kikku).[1]
• Bikaso Combo (ビカソコンボ, Bikaso Konbo) is a decapods-themed combo form of OOO in a video game Kamen Rider: City Wars, as part of the 10th anniversary of Kamen Rider OOO. It uses three cetapods-themed Core Medals: The orange colored Shrimp (エビ, Ebi) Core Medal that provides the Shrimp Head (エビヘッド, Ebi Heddo), the magenta colored Crab (カニ, Kani) Core Medal that provides Crab Arms (カニアーム, Kani Āmu), and the violet colored Scorpion (サソリ, Sasori) Core Medal that provides the Scorpion Legs (サソリバッタ, Sasori Reggu).[2]
• Saramiuo Combo (サラミウオコンボ, Saramiuo Konbo) is a marine fish-themed combo form of OOO, exclusive to SO-DO CHRONICLE KAMEN RIDER toy series, as part of the 10th anniversary of Kamen Rider OOO. It uses three Core Medals used by Kamen Rider Poseidon: The cyan colored Shark Core Medal that provides the Shark Head (サメヘッド, Same Heddo), the blue colored Whale Core Medal that provides Whale Arms (クジラアーム, Kujira Āmu), and the red colored Wolf Fish Core Medal that provides the Wolf Fish Legs (オーカミウオバッタ, Ōkamiuo Reggu).[3]
• Tamashī Combo (タマシーコンボ, Tamashī Konbo) is a Kamen Rider anniversary-themed form of OOO, which was only used in OOO, Den-O, All Riders: Let's Go Kamen Riders. Aside keeping the Hawk Medal's head, it uses an Imagin Core Medal that provides Imagin Arms (イマジンアーム, Imajin Āmu), and a Shocker Core Medal that provides Shocker Legs (ショッカーレッグ, Shōkā Reggu). Each two last Core Medals were origination from the essences of Momotaros and a Shocker Greeed respectively. This Combo's Scanning Charge is a surge fist projectile called the Tamashī Bomber (魂ボンバー, Tamashii Bonbā).

Eiji Hino is portrayed by Shu Watanabe (渡部 秀, Watanabe Shū).

Ankh (アンク, Anku) is a bird-type Greeed who believes he has the right to take whatever he wants, a dishonest wildcard who sees people for their flaws and is at odds with the other Greeed. As revealed in the Kamen Rider OOO novel, after the King removed his tenth Core Medal to finalized his creation 800 years before the events of the series, Ankh met a blind girl and created a Yummy to restore her sight out of empathy of having his own senses distorted. But Ankh regrets his decision as the girl died in horror that her sight came at the cost of people that the Yummy murdered for their eyes. Honoring the girl's last request to protect people, Ankh sided with the King to battle the other Greed until he was betrayed by the original OOO taking his Core Medals. When the king is overwhelmed by the Medals' power, it resulted in the Greeed being sealed away, including Ankh's severed right forearm which held the Core Medal containing his consciousness. With the rest of body separately sealed and mummified, Ankh lost most of his power.

When the Greeed were unsealed in the present, Ankh could not complete reform his body and instead steals the other Greeed's Core Medals to have them handicapped. But he loses one of his two remaining Hawk Core Medals when Eiji takes it by accident, initially intending to regain it before enlisting Eiji as the new Kamen Rider OOO for his agenda. But as Eiji turned out to be not so easy to manipulate, Ankh reluctantly cooperate with Eiji to save lives on the condition that they gather Cell Medals. Ankh also takes the body of the half-dead detective Shingo Izumi as a temporary host while providing the human with life support, allowing him to fully experience sensations while growing envious of humans. Overtime, Ankh undergoes a change in personality as he finds himself unable to harm Hina and Eiji without a substantial reason.

Even though he managed to regain some of his Core Medals, Ankh eventually learns the reason is because of the rest of his body developed into a being of its own. As both he and other half seek to absorb each other, which weakens his hold on Shingo, Ankh assumes that the weaker half would be consumed once he and Ankh (Lost) are reunited. While Ankh is eventually absorbed by his other self, the fusion is incomplete as he continues to defy Ankh (Lost) and passed a Taka Medal to Hina before being absorbed. After Eiji destroy Ankh (Lost) along with a full set of Ankh's Medals in OOO Putotyra Combo form, Ankh reconstitutes himself in a form resembling Shingo's possessed state. While Ankh regained his full power, the loss of one set of the Core Medals weakens Ankh as he possesses Shingo and takes his Hawk Core Medal from Eiji while siding with Maki on the condition to become the vessel for all the other Core Medals. After reviving Uva and feigning to have sided with the Greeed, counting on Eiji's new-found ability to destroy Core Medals, Ankh formulates a reckless plan to have OOO eliminate them so he can use their remaining Core Medals to fully fuse Shingo's body with his mind so he can become a truly conscious being. The scheme involves Ankh giving the other Greeed all their Core Medals back unconditionally, a result of being spoiled by his experiences with human senses while disgusted with his fellow Greeed.

But when Ankh confronts Eiji as he slowly turns into a Greed, he finds himself unable to kill him due to their history and his newfound capacity for feeling deeper emotions. This convinced Ankh to turn on Maki, who retaliates by taking the Core Medals he took from the killed Greeed while damaging the Hawk Core Medal containing Ankh's consciousness as it would eventually shatter. Ankh accepts his death with serenity before joining Eiji in their final battle against Maki. When the Kyouryu Greeed manages to negate Putotyra Combo, Ankh gives Eiji his last three Core Medals to prevent him from going rampage with his purple Core powers, disappearing and allowing Eiji to assume Tajadol Combo. His spirit fights alongside Eiji against the Kyouryu Greeed as they defeat Maki as he and the Core Medals are sucked into a black hole. As Eiji falls back to earth, Ankh appears to him as his disembodied arm and expresses his gratitude to him and others for allowing to live and die as a human while having into half of his shattered Taka Medal. The other half appears before Hina in a brief manifestation of his Shingo-like body, with Hina giving it to Eiji as he resumes his wanderlust with the hope of somehow reviving Ankh.

In the events of Mega Max, Eiji learns that he somehow found a way as Ankh arrives from the future to help him with Kamen Rider Poseidon. Eiji comes close to the method in during Heisei Generations Final crisis when he temporary revived Ankh through a replica body created by Kaisei Mogami.

In his true form, known as Ankh (Greeed) (アンク（グリード態）, Anku (Gurīdo-tai)), Ankh possessed abilities similar to OOO's Tajadol Combo and can create bird-themed Yummy that attack people to extract an attribute which they later feed to their host, much like a mother bird feeding her chicks. Ankh is forced to rely on human hosts like Shingo to move about as he could not fully recreate his body at the time, causing the host's hair to develop a peculiar style with a dull blonde color. Ankh can remove himself from Shingo's body on occasion, though he must reattach himself within ten minutes to keep Shingo alive. Ankh also uses Shingo's iPhone 4 and an iPad to gather information on the current era as well as to keep track of the ownership of the Core Medals, receiving the O Medal Holder from Hina to store Core Medals in.

The name "Ankh" comes from the Hindi word for "eye" (आँख ā̃ṅkh), as in a hawk's eye. His name was originally planned to be "Ash" (アッシュ, Asshu) from the Japanese word assuru (圧する, "to oppress" or "to dominate").[4]

Ankh is both voiced and portrayed by Ryosuke Miura (三浦 涼介, Miura Ryōsuke).[5]

Hina Izumi (泉 比奈, Izumi Hina) is Shingo's sister, who for some reason has superhuman strength, which she is a bit embarrassed about. She began working at the Cous Coussier restaurant as the Greeed awaken, worried for her brother's well-being when she eventually learns of the incident he was in. To prevent her from worrying, Eiji sends her a text message using Shingo's cell phone stating Shingo is on an undercover mission and won't be home for a long time. Eiji later tells her the truth, while promising to save her brother. Eventually, realizing his reason of looking after Ankh, Hina convinces Eiji to work at the Cous Coussier so she can care for her brother's body. She often uses her super strength to keep Ankh in line if he begins to treat her brother's body poorly or when he does something she does not agree with. Ankh does not like her and the two often argue, with only Hina's bizarre strength allowing her to win arguments. Hina eventually comes to realize she has been relying on Eiji's need to help to an unhealthy degree, and is taking steps to ensure Eiji does not blindly sacrifice himself for other people's sakes. After much contemplation, Hina also realizes she has come to care for Ankh, and wants both Ankh and Eiji, as well as her brother, to make it out of the Medal conflict alive. During the events of Super Hero Taisen, after Eiji was seemingly killed, Hina joined forces with Daiki Kaito, and the Gokaigers' Joe Gibken and Don Dogoier to solve the reason while Tsukasa Kadoya and Captain Marvelous are attacking each other.

Hina Izumi is portrayed by Riho Takada (高田 里穂, Takada Riho).

Kousei Kougami (鴻上 光生, Kōgami Kōsei) is the eccentric president of the Kougami Foundation. Well versed in the history of OOO and the Core Medals, he has anticipated the arrival of the Greeed and has amassed several Cell Medals and artifacts relating to the Greeed and OOO. He loves baking cakes, commonly birthday cakes, and has built his office over a bakery. He always has a record player in his office, usually playing "Happy Birthday", believing that the birth of all things, good or bad, is a thing of beauty. Any items he has sent to Kamen Rider OOO typically fit this belief, normally referred to as 'presents' and wrapped up as such. Kougami is easily excited and becomes incredibly enthusiastic when it comes to the OOO/Greeed conflict and the birth of new developments, shouting an emotional "splendid!" (素晴らしい！, subarashii!) at things that please him. He also has a habit of shouting "happy birthday!" whenever something new happens. Kougami believes that desires are the purest and most powerful energy source in existence, playing a major role in the evolution of life on Earth. This belief is to the extent of encouraging all around him to succumb to their own desires and do whatever they want as long as it does not interfere with his own desires. He sees Kamen Rider OOO, one bound for godhood, to be the means to ensure an unlimited supply of energy. To that end, Kougami manages to outwit Ankh into having him and Eiji work for him with a 60% Medal payment for the use his company's gadgets and equipment in order to achieve his lifelong work. Eventually, he has Kiyoto Maki develop a Kamen Rider with the ability to use and gather Cell Medals: Kamen Rider Birth. He eventually figures out that Maki is secretly working with the Greeed Kazari and threatens to fire him, causing Maki to destroy his lab and take everything he could, including the purple Core Medals. Kougami wishes to have the purple Core Medals destroyed as soon as possible, as what they represent goes directly against the goals he is trying to accomplish. Eventually, it is revealed that he is the one who awakened Ankh (Lost) by stealing one of his Core Medals.

He is revealed to be a descendant of the king who became the first Kamen Rider OOO, during Kamen Rider OOO Wonderful: The Shogun and the 21 Core Medals.

In Movie War Mega Max, it is revealed that Kougami is researching on creating new Core Medals that run on desire power alone before he gave the Poseidon Driver to Michal 40 years later.

Kousei Kougami is portrayed by Takashi Ukaji (宇梶 剛士, Ukaji Takashi).

Erika Satonaka (里中 エリカ, Satonaka Erika) is Kousei Kougami's personal secretary, often procuring cakes for him and seeing things from a business point of view. She also goes out of the office to run errands as instructed by Kougami, able to hold her own in a fight against a Yummy. Despite being Kougami's usual cake taster, Satonaka actually prefers spicy foods. Since Goto became the new Kamen Rider Birth, Satonaka becomes his support, even though she is actually his superior in the Kougami Foundation, carrying both her own Birth Buster to provide backup and a suitcase holding Cell Medals, loaded spare Bullet Pods, and Candroids. Much to Goto's chagrin, Satonaka is often late in arriving to the scene of a Yummy attack because of her obsession with her appearance, which leaves him at a disadvantage when he runs out of ammo for the Birth Buster.

Erika Satonaka is portrayed by Mayuko Arisue (有末 麻祐子, Arisue Mayuko).

Kamen Rider Birth (仮面ライダーバース, Kamen Raidā Bāsu) is an exoskeleton suit created by Kiyoto Maki. It is powered by Cell Medals, as opposed to OOO's Core Medals, using a Birth Driver (バースドライバー, Bāsu Doraibā) to transform. The user will a machine gun called Birth Buster (バースバスター, Bāsu Basutā), which requires amount of Cell Medals they have to shoot.

Birth's primary system is summon the Cell Medal-based weapons called Birth CLAWS (バースクローズ, Bāsu Kurōzu). Summoning all CLAW weapons allows the user to become Kamen Rider Birth Day (仮面ライダーバースデイ, Kamen Raidā Bāsu Dei).

Birth also has a prototype counterpart called Kamen Rider Birth Prototype (仮面ライダーバース・プロトタイプ, Kamen Raidā Bāsu Purototaipu). However, unlike its complete counterpart, it can only summon the Birth CLAWS weapons Breast Cannon and Crane Arm.

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. Although having had initially used a prototype version of Kamen Rider Birth system, he eventually succeeds his mentor Date, becoming the current user of its complete version's system.

Shintaro Goto is portrayed by Asaya Kimijima (君嶋 麻耶, Kimijima Asaya).

Akira Date (伊達 明, Date Akira) is a young combat medic who traveled the world before returning to Japan and being hired to become the first user of the Kamen Rider Birth system. He prefers getting his job done perfectly, rather than enjoying what he does.[6] Eventually, Date leaves Japan to undergo a life-saving surgery, returning some time later after the surgery was success and becoming the current user of the prototype Kamen Rider Birth system.

Akira Date is portrayed by Hiroaki Iwanaga (岩永 洋昭, Iwanaga Hiroaki).[6]

Kazari (カザリ) is the feline Greeed, an arrogant schemer who is able to move at fast speeds and create mini cyclones, able to use his dreadlocks as tendrils while in his complete form. Having lost the Tiger Core Medal to Ankh, Kazari assumes the form of a silver-haired young man in a yellow checkered blazer to blend in with society. However, of the five Greeed, it would appear he had the least missing Medals when the Greeed were released, seemingly only missing his Tiger Core Medal and the Lion Core Medal. His cat-based 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 can finally reach their complete form and consume the host. After realizing that there are others involved in finding the Core Medals besides them and Kamen Rider OOO, Kazari leaves the other Greeed to learn more of the third party. As a result, Kazari meets Kiyoto Maki and sets up a deal with him in hopes of finding his missing Core Medals, diverting from the Greeed's goal of consumption to one of evolution. This new ideology led to Kazari tricking Gamel into absorbing most of Mezool's Core Medals along with some of Uva's in order to see what would occur from a Greeed acquiring more than nine Core Medals. After the experiment, Kazari absorbed three of Mezool's Core Medals and two of Gamel's to undergo a controlled evolution, augmenting his powers with water- and gravity-based powers while able to create stronger hybrid Yummy with the attributes of those created by Mezool and Gamel. Using his new powers, Kazari manages to get all but one of his Core Medals back to reach his complete form before losing his Lion and Cheetah Core Medals to Eiji.

He eventually recruits Ankh (Lost) to his side while convincing Maki to sever his ties to the Kougami Foundation. This intention changes somewhat after deducting that Uva is trying to revive their fallen brethren, and he decided to assist Uva by faking that he lost Mezool's and Gamel's Core Medals to Uva. After Uva revives Gamel and Mezool, Kazari talks the two into joining his side and help him in destroying Uva. When Ankh joins forces with the Greeed with a revived Uva, he was notably upset that his plans are falling apart and that he is no longer the second-in-command of the group, to the point where he picked a fight with Ankh to blow off steam. Kazari is forced to play along until he manages to regain his Core Medals from Kamen Rider OOO by tricking Gamel into being a distraction and use his full power to take the other Greeed's Core Medals while heavily damaging Kamen Rider Birth. After Kamen Rider OOO Putotyra Combo damages one of his three Lion Core Medals, which happens to hold his consciousness, a wounded Kazari limps away before being found by Maki who assumes his Greeed form and rips out his remaining intact Core Medals. Kazari is then left to die, lamenting of never achieving his desire to have everything, as he breaks down into Cell Medals and his unstable Lion Medal shatters with only eight of his Core Medals were left in existence before they are sucked into the black hole that emerged from the Kyouryu Greeed's body.

The name "Kazari" comes from the Japanese word kazaru (飾る, "to decorate"),[4] as his Yummy's original method was engulfing the victim as the desires are fulfilled.

Kazari is portrayed by Taito Hashimoto (橋本 汰斗, Hashimoto Taito).[10][11]

Uva (ウヴァ) is the insect Greeed, the most hot-headed of his kind, able to jump long distances and discharge lightning from the claws on his right arm and the horns on his head. Having lost more Medals than some of the other Greeed, Uva is the first to track down Ankh to regain his Grasshopper and Mantis Core Medals from him. He assumes the form of a young man who wears a green leather jacket in order to blend in with society. His insect-based Yummy pull themselves out of the bodies of certain humans, then seek out and physically consume the object of their progenitor's desire before molting into their complete forms. However, starting with his Swallowtail Yummy, this has changed to carrying out the desire of their host instead, though taken to an extreme fashion, and Uva typically remains in contact with the host to some degree. Uva has been the only Greeed who bothered creating the weaker Waste Yummy (屑ヤミー, Kuzu Yamī). In the aftermath of Kazari's scheme with Mezool and Gamel undone by their own Core Medals, Uva decides to act on his own so he can find his own form of evolution through the Core Medals while creating the Waste Yummy to do his bidding. However, though he manages to take some of Gamel's and Mezool's Core Medals after the destruction of the Mega Greeed, Uva has not absorbed them into his body like Kazari. Instead, he has started seeding people with his Waste Yummy, producing a massive amount of Cell Medals for him to absorb to drastically increase his power while attempting to resurrect the two fallen Greeed. Though Uva succeeds reviving Gamel and Mezool, they turn on him as they, Kazari, and Ankh (Lost) destroy Uva's body. However, Uva's sole Stag Beetle Core Medal manages to latch onto a man named Kusada, using him as a human host before Ankh finds him and uses his Yummy to help Uva recreate his body. Supporting Ankh in his fight with Kazari, Uva manages to regain the Core Medals Kazari took from him and later gets all but one of his Grasshopper Core Medals back prior to Maki giving it to him. Assuming his complete form, Uva proceeds to overpower the Kamen Riders. When Kamen Rider OOO returns, using the King's Medals to fight as Tatoba Combo, Uva is ultimately mortally wounded in the fight, but Maki intervenes by throwing the Core Medals into him. He initially thanks the doctor for saving him, but eventually runs away due to Maki keep throwing extra Core Medals into him, causing him to start to destabilize. Though he attempted to fight the extra Core Medals, Uva is forcefully transformed into the Medal Vessel Chaos Form (メダルの器 暴走形態, Medaru no Utsuwa Bōsō Keitai), turning into the vessel of desire by converting all consumed matter into Cell Medals while creating Waste Yummy as a side effect. The Medal Vessel is eventually destroyed as Uva's Core Medals are all sucked into the black hole that emerged from the Kyouryu Greeed's body.

The name "Uva" comes from the Japanese word ubau (奪う, "to snatch away"),[4] as Uva's Yummy steal the source of desire from their surroundings, making themselves stronger.

Uva is portrayed by Yūsuke Yamada (山田 悠介, Yamada Yūsuke).[10] In the music video for "Anything Goes!", Uva makes a cameo as he fights Kamen Rider OOO.[12]

Gamel (ガメル, Gameru) is the heavy animal Greeed, physically the strongest of the four, yet has the mentality of a dimwitted spoiled child that makes him unable to work well with others normally save Mezool, whom he has an attachment to. Other than his brute strength and gauntlet armored fists, Gamel also can form a long trunk from his face to use as a weapon and gravity manipulating abilities. But in his full form, Gamel can turn anything he touches into Cell Medals. He is incomplete due to his Core Medals missing, only having five left by the time he was awakened. His human form is a young man who wears a grey mesh shirt over a black undershirt. In human form, he is often seen eating snacks although like any other Greeed, has no sense of taste and would even eat the inedible. Unlike the other Greeed, Gamel uses his body to create his large animal-based Yummy by inserting a Cell Medal into his own forehead upon observing a particular behavior he wants to mimic, thus satiating his own desires with the created Yummy being composed of a single Cell Medal. Because of his easily duped nature, Gamel was used as the subject of an experiment by Kazari, who gave him most of Mezool's Core Medals along with several of Uva's. The resulting 14 Core Medals seemingly restored his full form, but Gamel suffered from energy overload as a result of not having nine Cores of his own to maintain the power before Mezool absorbed him. After Mezool was destroyed, Gamel's Core Medals are divided among the surviving Greeed, with Ankh claiming one Gorilla Core Medal. Uva later manages to revive Gamel, assuming that he was taking a long nap, but he follows Mezool on siding with Kazari and Ankh (Lost). Later, after Ankh gives him back his Core Medals to assume his complete form, Gamel is shocked to discover that Mezool no longer wants him around, only managing to find her after she had been fatally wounded in a fight with Kamen Rider OOO. Knocking the Kamen Riders away, Gamel spirits one of Mezool's remaining Electric Eel Core Medals in a futile attempt to recreate her using humans to rebuild her body. However, two of Gamel's Core Medals are heavily damaged by Maki, eventually manifesting after Gamel takes a point blank range double Cell Burst from Kamen Rider Birth's and Birth Proto Type's Breast Cannons. He breaks down soon after, with only seven of his Core Medals were left in existence before they are sucked into the black hole that emerged from the Kyouryu Greeed's body.

The name "Gamel" comes from the Japanese word gameru (がめる, "to pilfer"),[4] as Gamel uses others' desires to create Yummy from his own body.

Gamel is portrayed by Hiroyuki Matsumoto (松本 博之, Matsumoto Hiroyuki).[10][13]

Mezool (メズール, Mezūru) is the aquatic animal Greeed, the only female of the group with the ability to generate torrents of water from her hand and possessing great agility, able to convert her body into a liquid at her full power. Though incomplete due to some of her Core Medals going missing, Mezool appears to be the most kind of the Greeed as her methods can provide enough Cell Medals for both herself and the other Greeed. She serves as a mother figure to the others, as her desire is to know and feel true love, reflecting in her relation to Gamel and her human form of a high school-aged girl. Her marine life-based Yummy, which first become roe-like eggs, feed indirectly off the human's desire while forming a "nest" that incubates over a period of time while the human indulges their desire. Their presence mostly concealed until the eggs hatch into their complete forms, either with one Yummy at a time or all eggs hatch into an army, compelled to return to Mezool and break up into many Cell Medals for her and the Greeed to ingest. After being tricked by Kazari as he takes all but one of her Core Medals, she finds herself on the run from Uva before finding Gamel and absorbing him to regain her Core Medals as well as any other Core Medals in Gamel's body. Not having all of her Core Medals to contain the power, her seemingly complete form ended up being just as unstable before Maki adds two of Uva's Core Medals and several thousand Cell Medals. The additional energy forces the Greeed to become a Mega Greeed. As a result of becoming a Mega Greeed Out of Control (巨大グリード暴走態, Kyodai Gurīdo Bōsōtai) due to the unstable power within her, her new leviathan-like body having heavy animal characteristics due to the influence of Gamel's Medals, Mezool becomes a mindless monster with an obsession to consume everything in sight. With assistance from Kamen Rider Birth, Kamen Rider OOO retrieves Uva's two Core Medals from the Mega Greeed's body and destroys her with Gatakiriba Combo. Mezool's Core Medals are then divided among the remaining Greeed, with Ankh claiming one Electric Eel Core Medal. After Uva manages to revive her, Mezool sides with Kazari's group after suffering defeat at the hands of Kamen Rider OOO Putotyra Combo, to escape destruction once again now at the hands of Kazari and Ankh (Lost) as well as so she can regain the rest of her Core Medals. Later, after Ankh gives her back her Core Medals to assume her complete form, spurred by Maki knowing it was a façade, Mezool leaves Gamel in order to achieve her desire. To that end, she proceeds to abduct mother/child pairs and sealing them in her Yummy eggs, sucking both the love and life out of them. With her full power, Mezool is able to counter Kamen Rider OOO Latorartar Combo before he uses the Toride Vendor and the Medagabryu to shatter a full set of her Core Medals. Mezool then dies as Gamel arrives in her final moments, with only six of her Core Medals left in existence were left in existence before they are sucked into the black hole that emerged from the Kyouryu Greeed's body.

The name "Mezool" comes from the Japanese word mezuru (愛ずる, "to love"),[4] as it reflects Mezool's desire while her Yummy grow from the obsessions of the host.

Mezool is voiced by Yukana (ゆかな),[10] while her human form is portrayed by Honoka Miki (未来 穂香, Miki Honoka).[14][15]

Ankh (Lost) (アンク（ロスト）, Anku (Rosuto)) is a Greeed that came into being when Ankh transferred the Hawk Core Medal containing his mind into his right arm before it was severed from the rest of his body when he and the other Greeed were sealed. The body ended up in a state of suspended animation, developing into separate being with childlike mind and desire to become whole. Ankh (Lost) awakens when Kougami extracted a Condor Core Medal, traveling to Japan in search of Ankh and making himself known after a series of bird Yummies he created which act on his desire to find Ankh. Ankh (Lost) later allies himself with Kazari and Maki, replicating the form of young boy as his human guise while his personality gradually develops into one similar to Ankh's. Combined with the tutoring from Kazari and the other Greeed, Ankh (Lost) created the Gamecock Yummy in a complex and very successful plan to reabsorb his other half while his guard was down.

Despite absorbing Ankh, Ankh (Lost) finds other's self is continuing to resist as he weakened his regeneration by secretly giving Hina a Hawk Core Medal at the last second. Ankh (Lost) is eventually destroyed when Kamen Rider OOO Putotyra Combo goes berserk and destroys three red Core Medals that were the foundation of his existence, leaving two of each of Ankh's Core Medals remaining until all but a broken Hawk Core Medal are sucked into the black hole that emerged from the Kyouryu Greeed's body.

Compared to the original, Ankh (Lost) refers to himself with the humble pronoun "Boku" (僕), as opposed to the Ankh's boastful "Ore" (俺), and retains almost all of Ankh's powers with abilities similar to OOO's Tajadol Combo. Additionally, his true form resembling Ankh's Greeed form with the right side of his body incomplete, Ankh (Lost) can create bird-themed Yummy that attack people to extract an attribute which they later feed to their host, much like a mother bird feeding her chicks.[16]

Ankh (Lost) is voiced by Miyu Irino (入野 自由, Irino Miyu) while his human form is portrayed by Hikari Tobita (飛田 光里, Tobita Hikari).

Giru (ギル) is a dinosaur Greeed who only appears in Kamen Rider × Kamen Rider OOO & W Featuring Skull: Movie War Core. During the events of Movie War Core, he creates a male Pteranodon Yummy to arrange the creation of Kamen Rider Core and the resulting doomsday from the monster's creation. He is originally in an inactive state prior to the series, as the ten Core Medals that comprise him were sealed away before being found by the Kougami Foundation and locked up because of the Medals' destructive power. However, they were stolen by Kiyoto Maki after severing ties with the Foundation. Five of the Core Medals sense the presence of Kamen Rider OOO and enter Eiji Hino's body, while the other five were inserted into Doctor Maki by Kazari. Eiji's implanted Core Medals give him the ability to detect Yummy like Ankh can, with his eyes flashing purple whenever this happens or when the Medals otherwise take over his body, and later, when he consciously summons the purple Core Medals; while Maki's allow him to use Cell Medals to create both dinosaur-based and mythical animal-based Yummy. The Yummy created by the Purple Core Medals are made using inanimate objects that represent the end of a desire, such as broken dreams. Though he is originally reluctant to be in the same area as Eiji under the notion that Medals' full power would be invoked, Maki decides to take advantage of Eiji without Ankh while presenting how far his body has undergone Greeedification before he completely turns into a Greeed soon after.

The name "Giru" comes from the Japanese word uragiru (裏切る, "to betray"), as his Yummy are the opposite of other Greeeds' Yummy by destroying desire rather than embodying it.

Giru is voiced by Kenji Hamada (浜田 賢二, Hamada Kenji). While the character is referred to by the name "Giru" in the film, Hamada is credited solely as the voice of the "Dinosaur Greeed" (恐竜グリード, Kyōryū Gurīdo) in the film's credits.

Nobunaga (ノブナガ) is the primary antagonist of the Kamen Rider OOO: Nobunaga's Desire segment of Kamen Rider × Kamen Rider OOO & W Featuring Skull: Movie War Core. Nobunaga is a Cell Medal-based homonculus created by the Kougami Foundation from the mummified remains of the conqueror Oda Nobunaga, running off scared and confused. Assuming the form of the Greeed-like Armored Warrior Inhumanoid (鎧武者怪人, Yoroimusha Kaijin), Nobunaga targeted those descended from the ones who arranged his death while Eiji looked after him and taught him about the modern world before his services are no longer needed. However, Nobunaga's body was suffering a Cell Medal breakdown before he is forced to absorb the three Black Core Medals by Kiyoto Maki to become a mindless Greeed before he is defeated by Kamen Rider OOO Sagohzo Combo After his defeat, Nobunaga asked Eiji to give Yoshino a flower from him before he disperses into Cell Medals while the three Black Core Medals fly into the distance, resonating with the Memory Memory.

Nobunaga is portrayed by Kengo Ohkuchi (大口 兼悟, Ōkuchi Kengo). The Armored Warrior Inhumanoid form is voiced by Keikō Sakai (酒井 敬幸, Sakai Keikō). In promotional materials, the Armored Warrior Inhumanoid was referred to as the "Armored Warrior Greeed" (鎧武者グリード, Yoroi Musha Gurīdo).

Yoshino Akechi (明智 よしの, Akechi Yoshino) is a supporting protagonist in the Kamen Rider OOO: Nobunaga's Desire segment of Kamen Rider × Kamen Rider OOO & W Featuring Skull: Movie War Core. She is a senior friend of Hina and a descendant of Akechi Mitsuhide, the legendary samurai who betrayed and killed Oda Nobunaga. She dreams of becoming a professional ballet dancer and Nobunaga falls in love with her because of her dancing when he was unable to kill her like the others. When she breaks her leg as a result of Nobunaga not taking her rejection well, her dashed hopes of ever dancing again are used to create the female Pteranodon Yummy. Nobunaga gives his last energy in order to heal her leg to live her dream.

Yoshino Akechi is portrayed by Sayako (彩也子).[17]

The Shocker Greeed (ショッカーグリード, Shokkā Gurīdo) is a Greeed created by Shocker whose Core Medal was found by Shocker and converted into the Shocker Core Medal. Originally, Shocker was never able to utilize the Shocker Core Medal's power in their schemes. However, a Cell Medal that Ankh left behind in the past during his attempt to use the Den-Liner to get his hand on the other Greeeds' Core Medals provided Shocker with the means to bring their creation to life and cause the events of OOO, Den-O, All Riders: Let's Go Kamen Riders to occur. Defeating Kamen Riders #1 and #2 in the past, the Shocker Greeed allowed Shocker to proceed with their plans to rule the world. But in the present, having faked their resulting brainwash thanks to a time paradox caused by the attempt to undo the monster's birth, the Double Riders manage to destroy the Shocker Greeed with their Double Rider Kick. Though Ankh obtained the Shocker Core Medal, it later dissolved.

The Shocker Greeed is voiced by Hideo Ishikawa (石川 英郎, Ishikawa Hideo).

Tokugawa Yoshimune (徳川 吉宗) is the eighth shogun of the Tokugawa shogunate of Japan, who roams freely through Japan disguised as a Samurai named Tokuda Shinnosuke (徳田 新之助). Tokugawa works alongside Kamen Rider OOO in the past to protect the city of Edo. During the battle with the Nue Yummy, he gives Kamen Rider OOO the orange Core Medals that was sent to him as a gift from Europe.

Tokugawa Yoshimune is portrayed by Ken Matsudaira (松平 健, Matsudaira Ken), who also played exactly the same role in The Unfettered Shogun. 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).

Gara (ガラ) is an androgynous orange-robed alchemist who was among the four that created the Core Medals for the King eight centuries ago along with the orange Core Medals, having intended to become "true OOO" (真のオーズ, Shin no Ōzu) by using the Core Medals to destroy the world and rule over what remains as King of the World (世界の王, Sekai no Ō). But the King killed Gara alongside the other alchemists once they fulfilled their commission, with Gara buried in Thuringia. Reawakened in June 2011 when Kougami unearths his tomb, Gara uses his alchemy to flip the area surrounding his tower from Germany over to Tokyo as he captures Kougami and Satonaka while possessing the body of Satsuki Wakaba (若葉 五月, Wakaba Satsuki). From there, seeing the world had not changed since his sealing, Gara takes the Greeeds' Core Medals and proceeds to use human desire to cause three time distortions in order to execute his doomsday scenario. He sends the Nue Yummy and his Knights to the time distortion leading into Edo to obtain the remaining Core Medal sets needed to complete his plan. However, falling for Kougami's trick, Gara's scheme to use human desire fails when his attempts to use Eiji's desire to his advantage damages the device.

Using the gathered Cell Medals when Kamen Rider OOO enters his tower, Gara assumes his true Greeed-like Inhumanoid Form (怪人態, Kaijintai) with extendable arms prior OOO manages to free Satsuki from the monster's body. Though being defeated when Kamen Rider Fourze arrives to double team the monster, Gara acquires Eiji's purple Core Medals to use all the Core Medal sets to transmute himself into the Mega Greeed-like Gara Dragon (ガラドラゴン, Gara Doragon) before being destroyed for good by all eight OOO Combos' Scanning Charges and Kamen Rider Birth's Breast Cannon.

Alchemist Gara and Satsuki Wakaba are both portrayed by Miki Sakai (酒井 美紀, Sakai Miki). As the Gara-possessed Satsuki, Sakai had her voice digitally deepened and altered for this role. In his true form, Gara is voiced by Ryūzaburō Ōtomo (大友 龍三郎, Ōtomo Ryūzaburō).

The Bells (ベル, Beru) are Harlequin-like triplet familiars created by Gara to serve him. One of the Belles is sent across the city with to gather human desire for her creator with her Chance Time proposition in three areas where she gives five million yen to anyone willing to have a Chonmage hairstyle for the rest of his or her life. Managing to reach two thirds of her goal, Belle attempts to finish the job by offering Eiji a Chance Time to return to modern Tokyo at the cost of everyone else around him ceasing to be. Eiji accepts on the condition that his family also be spared, and then reveals that he considers all the people present his "family", causing Belle to explode into Cell Medals.

The Bells are portrayed by Karin Ogino (荻野 可鈴, Ogino Karin).

Michal Minato (湊 ミハル, Minato Miharu) is a young man from the year 2050 who has the ability to transform into the heroic Kamen Rider Aqua (仮面ライダーアクア, Kamen Raidā Akua) by using the Aqua Driver (アクアドライバー, Akua Doraibā), which uses a liquid called Manas Aqua (マナスアクア, Manasu Akua). Though his powers are based around water, Michal is ironically scared of water. Michal absorbed Cell Medals and Core Medals that came out of a mysterious black hole, which later creates Kamen Rider Poseidon. Michal transforms into Kamen Rider Aqua to help Kamen Rider OOO to defeat Poseidon. After the battle, he gives Eiji the Super Hawk, Super Tiger, and Super Grasshopper Core Medals from the future before going back to his time to protect it after realizing what it means to be a Kamen Rider. Michal later returns to the present during the events of Kamen Rider Zi-O, getting caught up in the titular protagonist's final battles where he died protecting him.

Kamen Rider Aqua's Rider Kicks are called the Oceanic Break (オーシャニックブレイク, Ōshanikku Bureiku) and the Aqua Vortex (アクアヴォルテクス, Akua Vorutekusu). Kamen Rider Aqua has a personal jet ski called the Aqua Miraider (アクアミライダー, Akua Miraidā).[18][19][20] Kamen Rider Aqua is designed to resemble the first two Kamen Riders 1 and 2, with a simpler design and the tear-stain–like lines on his mask.[21] Michal also possesses a prototype version of the Time Mazine that appeared in Kamen Rider Zi-O for time travel purposes.

Michal Minato is portrayed by Atsushi Arai (荒井　敦史, Arai Atsushi).

Kamen Rider Poseidon (仮面ライダーポセイドン, Kamen Raidā Poseidon) is a Greed-like entity formed from the Cell Medals and Core Medals within Michal's body, turning him evil 40 years into the future. As Michal, he is given three marine fish theme Core Medals (the cyan Shark (サメ, Same), the blue Whale (キジラ, Kujira) and the red Wolf Fish (オーカミウオ, Ōkamiuo) Core Medals) and a similar belt as the OOO Driver known as the Poseidon Driver (ポセイドンドライバー, Poseidon Doraibā), which he receives from the aged Kousei Kougami in his time. He then becomes able to transform into Kamen Rider Poseidon. Kamen Rider Poseidon uses a large crimson harpoon called the Deepest Harpoon (ディーペストハープーン, Dīpesuto Hāpūn) as a weapon. He then arrives to the present time in Michal's body to eliminate all Kamen Riders. The Kamen Rider Poseidon entity is eventually split from Michal's body in his Kamen Rider Poseidon form. Kamen Rider Poseidon is defeated by Kamen Rider OOO Tajadol Combo's Prominence Drop and Kamen Rider Aqua's Oceanic Break, his Core Medals taken for Kannagi to transform into the Super Gingaoh.

Kamen Rider Poseidon is voiced by Kenji Hamada (浜田 賢二, Hamada Kenji).