Mazinger Z vs Getter Robo is a special crossover manga by Yuichi Hasegawa, that was released alongside Super Robot Wars α. The manga depicts the titular mecha battling it out after an elaborate ruse by their enemies caused them to combat each other. At the same time, mysterious new pilot recruits for the Photon Power Lab are hiding a dangerous secret.
A battle is shown between the Earth Federation Army and the Dinosaur Empire. Mechs like Daitarn 3, Raideen the Brave, Grungust, and Giant Robo are doing their best to even the odds. In the midst of the battle, Getter Robo is slaying as many Mechasaurus until it is blindsided by a black fist to the chest. The fist belongs to none other than Mazinger Z. Emperor Gore is apparently is controlling Koji Kabuto and forcing him to fight the Getter Team. A huge battle starts between the two robots.
During the battle, they land on top of the Mechasaurus Dai. The Getter Team can no longer hold back or else they would die. Getter 2 drills into Mazinger's Pilder decapitating Koji. The Getter crew grieve as they come to terms of killing off an ally. However, the severed head grins while the headless body is still controlling Mazinger Z, continuing to attack the Getter. The fake Koji reveals himself to be none other than Count Brocken.Earlier back at the Earth Federation Army base, three new mechs have just been constructed: Million α, Baion β, & Daion γ. Koji ogles the three new voluptuous pilots as Sayaka pulls him away by the ear. The Alpha's crew composed of: Bullet, Kuhusha, Yuuki, & Carla decide to visit the Photon Lab. However, they discover that the Mazinger Z is being hauled off by four mysterious aircrafts. Inside the institute, all the staff are in a critically injured state and Koji and his friends have been captured.The three new female officers reveal themselves to be Gamia Q sisters, the 'daughters' of Baron Ashura. They interrogate Koji, even so far as to shred Sayaka's clothing and threaten to the tear her into pieces until he complies. But before they do, they see a figure in Koji's pilot suit. Two of the killer gynoids investigate while the last one stays behind. Suddenly, Bullet smashes through the window armed with a kendo sword. As the Gamia attacks a flinching Bullets, Koji jumps in to shield Bullet. With his ropes now cut, Koji grabs a chair and smashes it onto the guarding Gamia, sending her out the window. The sisters catch up to the mysterious figure who is revealed to be Carla. Yuuki and Kuhusha then spray the sisters with flamethrowers but this only got rid of their clothing. Boss Borot comes to the rescue and manage to grab one of the Gamia, but the android just bursts through the robot's fist. Sayaka in the Aphrodite A comes to Borot's rescue in response. One Gamia android manages to block off the hatch to the Oppai Missile but gets blown up in the process. The other one targets the cockpit but gets squashed by Aphrodite's hands. The last one manages to smash the Aphrodite's dome only be shot by Sayaka with her Photon Gun. As the heroes regroup, Boss asks how are they going to get Mazinger back with their mechs badly damaged. Koji then points to the three new constructed mechs.
Back over to the battle, Dr. Hell & Emperor Gore celebrate their victory over Getter Robo in their secret alliance. The Mazinger Team comes to the rescue with Koji in Baion, Sayaka in Million, and Boss in Daion. In the clash, Gore sends new Mechasaurus but they are quickly discarded by the Mazinger Team's superior skills and teamwork. Reinvigorated, but still heavily wounded the Getter Team gets back into the battle. Emperor Gore enlarges himself, then bursts out of Dai. One-by-one, the Mazinger mechs are defeated by this giant Gore.
In the brawl, Brocken in Mazinger manages to rip through Baion's abdomen but is then ambushed by Koji who breaks through the Pilder's cockpit. Koji throws Brocken out and reclaims Mazinger Z. Gore, still fighting the Getter begins to tell the history and suffering of the Dinosaurs and promise to enact revenge to the humans who stole the earth from. Getter is trapped between the clutches of Dai's carrier door. Musashi tells the other to escape through an Open Get leaving him to be crushed. He is then saved by Mazinger who teams up with the complete Getter Robo to defeat the monstrous Gore.
They use their chest blasters to wipe out the insides of Dai. Then they proceed to grab each of the two heads of the carrier Mechasaurus to slam them onto Gore. However he still lives vowing to take them down until his last breath. By combining their assault the mechs manage to bring Gore down. But he still has up more trick up his sleeve, which is to take Getter Robo with him as he leaps forward. Ryoma laments at Gore's will before firing one last Getter Beam to finish him off for good. Meanwhile Daitarn 3, Raideen, Giant Robo, & the Grungust with the rest of the Earth Federation Army finish the last of the Mechasaurus before congratulating on Koji & the Getter Team on their victory. However before the story ends the last page shows a bat-like figure has discovered Emperor Gore's head.