Activation! Mazinger!

'''Activation! Mazinger!''' is the official start of Mazinger Edition Z: The Impact!. It first started with an in media res for the series finale before going to the beginning.

Plot
Koji and Shiro Kabuto live with their grandfather Juzo Kabuto while mysterious murders go around their manor. Inspector Ankokuji investigates the murders while also acting as Juzo's bodyguard. In the meantime, Dr. Hell and Baron Ashura plan their attack on the Photon Power Laboratory with Ashura attacking the Kabuto Manor.

Synopsis
The series starts with a fallen Mazinger Z besides the Great General of Darkness. The narration then brings the audience to the beginning where it describes the Photon Power Lab and its research in Photonic Energy. Photonic energy can solve the energy crisis but also be used as a terrible weapon. Dr. Hell attempts to obtain this power and sends out Baron Ashura in the first wave towards world domination.

Under Prof. Yanosuke Yumi, the Photon Lab starts its experiments to use Photonic Energy to power Atami, much to the displeasure of Juzo Kabuto. Several men have been found dead around a house, with their faces cut vertically down. Inspector Ankokuji is investigating these murders noting how suspicious it is around the Kabuto Estate.

In the morning Shiro is startled by his grandfather, Juzo. Koji is making breakfast for everyone while enjoying their time together. A stranger watches the house from a distance before he is confronted by the police and proceeds to take them out. Juzo requests that his grandchildren come home a little early for something he wants to discuss with them. Riding to school on a new motorcycle with a touched up engine, the brothers bring up how their grandfather's patents give them all the money they'll need while Juzo has been working on a secret project. A young woman on a motorcycle spots the Kabuto brothers and decides to make contact with them while a boat full of delinquents want to fight them.

After Juzo's grandchildren leave, Inspector Ankokuji establishes that Juzo lived at the estate when observing him at the Kurogane House. When Juzo encounters the man from before, the man kills an officer. When Ankokuji arrives at the area, he sees the same cut but notices that the cop was not stationed at this jurisdiction. With one of their men down, Ashura decides to attack directly with a pair of Mechanical Beasts.

After school ended, Shiro is waiting for Koji but is kidnapped by Boss's his gang. Koji is notified and is challenged to a fight. Sayaka observing Koji decides to use one of her contingencies as she makes her giant machine move. Juzo tests out the laser defenses of his home on pigeons when Ankokuji approaches and is set on fire. Once inside, Ankokuji asks about the murders that have going around the Kabuto Manor. Ankokuji has been assigned as his bodyguard but notes that somebody else has been protecting him. Juzo does not mind this and just messes with the inspector as the lights go out. The Mechanical Beasts have damaged the energy transformers of the Photon Power Laboratory. Juzo goes down into his secret lab when Ankokuji gets attacked by mysterious men.

Koji at the meeting area confronts Boss who wanted to fight Koji to dominate the Atami High School area. Koji does not want to fight but when Boss insults his grandfather, Koji snaps beating up Boss while Shiro escapes from his ropes. Sayaka calls out to him saying that he and his grandfather are in danger. Boss uses the opportunity to attack but notices a giant robot off the cliff. Everyone drives off with Juzo contacting his grandchildren to get back quickly but more of the Talos attack. Sayaka helps them with her robot Aprhodite A as they race off.

With his home under siege, Juzo is forced to send the Hover Pilder to his grandsons before activating his secret project. With a Talos still on their tail, the Hover Pilder arrives for some much needed help. With Koji in the Pilder, Juzo releases his secret project to dock with the Pilder: Mazinger Z.