The Shocker Greeed is an eagle-like Greeed created by Shocker through a modified Core Medal known as the Shocker Medal and a Cell Medal Ankh accidentally left behind in the past when he and Eiji Hino were helping out the Taros and Kamen Rider New Den-O fight three Mole Imagin. A Shocker Combatant found the Cell Medal and presented it to his superiors where they used it to create the Shocker Greeed.
Shocker, in their many attempts at rising to power, discovered the Core Medals from 800 years ago, and modified one of the 10th Medals to become the Shocker Medal. However, Shocker was unable to make anything from it, as, despite their efforts, no Cell Medals were ever found in the original timeline.
But when a Cell Medal was dropped by Ankh when he followed New Den-O back to 1971, in an attempt to get the other Greeed's Core Medals without a fight, this all changed. A Shocker Combatman finds the Cell Medal and presents it to General Black, who in turn presents it to the Great Leader. The Great Leader lets the Shocker Medal absorb the Cell Medal, and the Shocker Greeed is born. After its creation, Shocker sent it's new Greeed into the field where it defeats Kamen Riders Ichigo and Nigo and brings them back to Shocker, who finally finish the brainwashing process they started on the Double Riders so long ago. With the two strongest soldiers they ever created now totally obidient, they move forward with their plans to rule the world. The Shocker Greeed assists as Shocker takes over most of the world.
When OOO and New Den-O are captured and stripped of their Rider Belts, the Shocker Greeed comes out of hiding for the first time in the present, as Shocker sees this as the solidification of their power. When the Junior Kamen Rider Squad, a group of children who went with Den-O and saw the good things done by Riders, rush the stage to return the OOO Driver to Eiji, the Shocker Greeed fights back without prejiduce. The crowd joins in to try and help, but stop when the voices of the Double Riders ring out and tell them to stop. The Shocker Greeed, thinking them brainwashed, relaxes and is confident that they will help and Shocker will become the new definition of justice.
However, when Kamen Rider OOO and Kamen Rider New Den-O attempted to prevent its creation by traveling to the past, it caused a time paradox. One of the boys, Naoki, is left in the past but grows up to join Shocker as a brilliant scientist. However, seeing his chance at last, he undoes the brainwasing when Eiji and Kotaro are about to be executed. He undoes the Double Riders' brainwashing and allows them to fight back in the present day. So, the Riders laugh in his face, and attack to get Eiji his Driver back, assembling together all the main Riders of both the Showa and Heisei eras through the power of people's memories. Ichigo and Nigo take on the Shocker Greeed in a final rematch, destroying the Greeed with a Rider Double Kick. The Shocker Greeed calls out the traditional Shocker "Banzai!", and explodes, Ankh taking its Medal at last. He presents it to Eiji to use in conjunction with the Imagin Medal created from Momotaros, to fight the Great Leader as OOO Tamashii Combo. However, once the Riders win, the Medal dissolves forever.
In the Kamen Rider OOO SIC Hero Saga, remnants of Shocker recreate the Shocker Greeed in a new form and sought it out on Kamen Rider OOO along with the Gel-Shocker and Destron Greeed. With help from Joji Yuki, the Greeed are destroyed, but their Medals are later used for the creation of Shocker OOO.
Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai
The Shocker Greeed is one of the most powerful kaijin in the Kamen Rider series, overpowering several Kamen Riders where the other Shocker kaijin eventually met their fates. As a Greeed created by a 10th Core Medal, it is much more powerful than the average incomplete Greeed. It has the ability to fly and shoot projectile attacks out of its fingers.
In the SIC Hero Saga, it gains the ability to assume a form similar to Shocker Rider Number 1, complete with the yellow scarf.