Pre-series
- 1211: The Greeed are created from the fifty Core Medals by humans who attempt to create life under the will of the King, the First Kamen Rider OOO, as part of his plan to achieve godhood. Though originally mindless, the five Greeed gained wills of their own after one Medal in each of the five sets was destroyed. They are beings without true life that crave endlessly, cursed with a void in them that can never be filled. They lack proper senses, resulting in bleak sensory input (e.g., colors are washed out, taste is nonexistent, sounds are muffled and distorted), as well as the inability to feel deeper emotions such as love. As such, the four other Greeed became bent on filling the void left in them by consuming everything obsessively in an attempt to experience what humans normally take for granted. However, they and part of Ankh were sealed by the King when the Core Medals consumed him and transformed him into a stone coffin.
- November 11, 1971: The Shocker Greeed is created as a result of a temporal incursion. In the altered timeline, Kamen Riders 1 and 2 are defeated by the Shocker Greeed and ostensibly brainwashed to serve Shocker. (Let's Go Kamen Riders)
Series2010
- OOO appears in Futo City, where he helps Kamen Rider Double by defeating the Luna Dopant. (Double The Movie)
2011
- April 1: In the altered timeline, Shocker's alliance prepares to complete its subjugation of the world. (Let's Go Kamen Riders)
- April 2: All the Kamen Riders return to defeat Shocker and destroy Rock Great Leader. (Let's Go Kamen Riders)
Post-series
- November 5, 2011: A meteor shower rains on Earth containing SOLU samples, one of which opens a wormhole leading 40 years into the future.
- November 6, 2011: Michal Minato possessed by Kamen Rider Poseidon emerges from the wormhole to challenge Kamen Riders of the past in battle, followed by a future incarnation of Ankh following his resurrection.
- November 7, 2011: Eiji helps Michal overcome his hydrophobia to become Kamen Rider Aqua, teaming up to destroy Poseidon. Michal and Future Ankh return to their time period via the wormhole, only for Eiji & Hina to be ambushed by Lem Kannagi of Foundation X, who takes Poseidon's Core Medals to give himself dominion over time as the Super Galaxy King.
- 2012: OOO is among the many Riders who apparently defeated by Captain Marvelous (Gokai Red), Emperor of Dai-Zangyack which seeks to wipe out the Kamen Riders, opposing Dai-Shocker led by Great Leader Tsukasa Kadoya (Kamen Rider Decade) who are hunting the Super Sentai. Infact, all the presumed deceased Riders and Sentai had been transported to the dimensional rift, from which they emerge to defeat the new Shocker-Zangyack Alliance. (Super Hero Taisen)
- 2013
- OOO joins in the battle against Space Crime Syndicate Madou's army of revived monsters. (Super Hero Taisen Z)
- OOO, among the first 15 Heisei Riders, is summoned to World within the Magic Stone, where he helps to defeat the evil wizard Amadum and his army of monsters. (''Wizard ep. 52-53)
- 2014: OOO participates in the battle to defeat the Underground Empire Badan, as well as the brief conflict between the Heisei Riders and Showa Riders. (Kamen Rider Taisen)
- 2015: In an Alternate Timeline where Shocker conquered the world in 1973, OOO serves Shocker before his brainwashing is reversed, joining the other Riders in the fight against Shocker before the timeline is restored. (Super Hero Taisen GP)
- 2018: OOO helps in the battle against Kaisei Mogami of Foundation X. (Heisei Generations FINAL)
- 2051: The active time period of Michal Minato, whose hydrophobia is detrimental to his transformation into Kamen Rider Aqua. Even with the Poseidon Driver and new Core Medals provided by the Kougami Foundation to let him fight without the Aqua powers, Minato’s lack of courage hinders him. A wormhole from 40 years prior infuses into him the Core Medals and Cell Medals from the implosion of the Medal Vessel, causing Poseidon to become a bloodthirsty Greeed possessing him.
