The Greeed are coin-based homunculi created from the fifty Core Medals 800 years ago by humans who attempted to create life. Though originally mindless, the five Greeed gain wills of their own after one Medal in each of the five sets was destroyed. As a result, the Greeed became bent on filling the void left in them by consuming the world before they were sealed by OOO. When the seal is removed, unable to recreate his body completely, Ankh manages to steal some of his fellow Greeed's Core Medals, so they would be handicapped as well while stating that the other Core Medals were lost to them during their imprisonment. As a result, the four Greeed use their Yummy to track down Ankh and regain their stolen Core Medals while using them to gather as many Cell Medals as needed to maintain their physical forms. After realizing how much humanity changed over the past 800 years, the Greeed assume human forms to blend into society. Each Greeed has three sets of Core Medals and are able to maintain their powers so long as they do not lose them all. Once they do, the armored portion of their forms that draws power from that Core Medal disappears while they "bleed" Cell Medals. If they only have one Core Medal left in their bodies, then they are forcibly reverted to human form and suffer terrible pain. The exception to that rule is Ankh, and Uva speculates that it is due to Ankh possessing other Core Medal types in his body. If a Greeed's body gains more than its nine Core Medals, its body will begin to destabilize from the power as the other Core Medals act as if they are its own. The end result of this is a Mega Greeed, an extremely powerful chimera-based monster. However, seeing the Mega Greed to be an ideal form, Kazari attempts to become a more stable version.
Uva 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. Having lost more Medals than some of the other Greeed, Uva is the first to track down Ankh to regain his Batta and Kamakiri 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. 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 Greed, Uva has not absorbed them into his body like Kazari. The name "Uva" comes from the Japanese word ubau, as Uva's Yummy steal the source of desire from their surroundings, making themselves stronger. Uva in Spanish means grape.
Kazari is the feline Greeed, an arrogant schemer who is able to move at fast speeds, as well as create mini cyclones. Having lost the Tora 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 Tora Medal and the Lion 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 them. 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 hope 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 a 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 himself 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 Yummies 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. The name "Kazari" comes from the Japanese word kazaru ("to decorate"), as Kazari's Yummy engulf the victim as the desires are fulfilled.
Gamel is the heavy mammal Greeed, and is the physically strongest of the four, yet has the mentality of a 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. He is incomplete due to his Core Medals going missing, only having five left. His human form is a young man who wears a grey mesh shirt over a black undershirt. 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 Medal. The name "Gamel" comes from the Japanese word gameru ("to pilfer"), as Gamel uses others' desires to create Yummy from his own body.
Mezool is the aquatic animal Greeed, the only female of the group with the ability to generate torrents of water from her hand and agility. 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 leader figure to the others, keeping Uva and Kazari in line while acting like a mother to Gamel. Mezool assumes the 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, finds herself on the run from Uva before finding Gamel and absorbs 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 as unstable before Mak's adding two of Uva's Core Medals and several thousand Cell Medals unto the Greeed causes her to become a Mega Greeed. As a result of becoming a Mega Greeed Out of Control 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 Birth, OOO retrieves Uva's two Core Medals from the Mega Greeed's body and destroys her. Mezool's Core Medals are then divided among the remaining Greeed, with Ankh claiming one Medal. The name "Mezool" comes from the Japanese word mezuru ("to love"), as Mezool's Yummy grow from the obession of the host.
Ankh (Lost) appears after a series of bird Yummy appear in the city, sent to attack Ankh and retrieve the Core Medals from him. Though only the left arm is visible during his early appearances, this Ankh actually consists of nearly all of his body except for his right arm, lips, and the crest on the the right side of his face, which are instead composed of blank purple skin. He was created 800 years ago when Ankh was betrayed by the original OOO, who in the act of sealing the other Greeed, ripped off Ankh's arm and the Core Medals containing his mind. The mindless body, sealed separately from the other Greeed, was in a state of rest in Europe for centuries, brewing the desire of recovering himself. A Condol Core Medal was ripped from his body by Kougami after having retrieved it during his trip to Europe mid-series, and the feeling of loss caused the body to awaken. Lacking the memories or personality of the original Ankh, Ankh (Lost)'s new personality is described as that of a baby bird looking desperately for its mother, continuously asking for the whereabouts of his other self and growing agitated when he detects his missing Core Medals. Ankh (Lost) is driven to absorb his other self and become whole again, though Ankh suspects any merger between them would consume the weaker one. Most of Ankh's abilities were preserved however, as during battle, Ankh (Lost) possesses all of the same abilities as Kamen Rider OOO's Tajadol Combo with roughly equal power, even able to perform his own variation of the Prominence Drop Scanning Charge. Additionally, Ankh (Lost) is still capable of producing bird-themed Yummy that attack people and then rob them of an attribute which they later feed to their host, much like a mother bird feeding her chicks. This Ankh allies himself with Kazari and Maki, taking on the human form of young boy dressed in red and black. Unlike the boy he copies, his right sleeve is tinted slightly purple. Overtime, Ankh (Lost) undergoes accelerated mental development, developing a more assertive personality and advanced mental capacity, beginning to act more like his other self. Combined with the tutoring from Kazari and the other Greeed, Ankh (Lost) created the Shamo Yummy in a complex and very successful plan to reabsorb his other half while his guard was down. Despite fully absorbing Ankh, Ankh (Lost) has still not been able to fully regenerate due to Ankh having secretly given Hina a Taka Medal at the last second. Their fusion is also incomplete as Ankh (Lost) could sense his other self still defying him. Though he seemingly managed to fully absorb Ankh, Ankh (Lost) is 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 Taka Medal are sucked into the black hole that emerged from the Kyouryu Greeed's body.
Giru is the dinosaur Greeed who first appears in Kamen Rider × Kamen Rider OOO & W Featuring Skull: Movie War Core. During the events of Movie War Core, he creates the two Pteranodon Yummy with one made out of the desire to collect memories of past Kamen Riders and the other from the desire to dance. The name "Giru" comes from the Japanese word uragiru ("to betray").
The Shocker Greeed is a Greeed created by Shocker from a Cell Medal and the Shocker Core Medal, which itself was created by Shocker from a Cell Medal left behind by Ankh in the past during the events of OOO, Den-O, All Riders: Let's Go Kamen Riders. The Shocker Greeed defeats Kamen Rider #1 and Kamen Rider #2 in the past and allowed Shocker to proceed with their plans to rule the world.