Great Mazinger (グレートマジンガー) is the sequel series to Mazinger Z. This series featured new protagonist Tetsuya Tsurugi and the titular mech, Great Mazinger in the fight against the Mycenae Empire. Unlike the original Mazinger Z manga, the Great Mazinger manga follows more closely to the anime storyline as if completely ignoring the Z manga.
The series begins after the battle against Dr. Hell with attacks from the Warrior Beasts. With the Mazinger Z overwhelmed by this new threat, it was almost destroyed until it was rescued by the Great Mazinger. With assistance from the Science Fortress Laboratory, Tetsuya Tsurugi and the Great Mazinger battle against the risen Mycenae Empire. With the defeat of military leader, Great General of Darkness peace had came for once a brief while.
The Empire brought Dr. Hell back from the dead as the new military commander and overpowered the Great Mazinger until the restored and strengthened Mazinger Z came back to fight. Koji and Tetsuya would fight together to bring down this threat with their robots and their allies. With a final assault on the empire, the Mazinger brothers emerge victorious.
While Great Mazinger did not have the same high ratings as its predessor, it was still very popular in its time; enough to spread several merchandize throughout Japan and high enough ratings to fund the creation of Grendizer. It was also very popular in broadcasts in Italy and several Latin American countries. The main robot also starred in several crossover films between sister series Getter Robo such as Great Mazinger vs. Getter Robo. The said robot also appeared in several related media such as the Mazinkaiser OVA and the Super Robot Wars games.