Season 1

A World War II scientist reawakens the robotic replica of a powerful android boy to fight as Metalder as the evil Neroz begins to send forth his troops to conquer the world.

Tsurugi tries to make sense of the world around him and his mission as Metalder even as Neros continues to target him for elimination.

As Tsurugi tries to gain further control of his mental functions and a search for friends, a warrior from the Armor Corp goes forth to target him.

Tsurugi researches more about Dr. Koga to find out more on who he is as multiple soldiers of God Neroz' army go forth to stop him.

The fair-playing gunman Topgunder decides to take matters into his own hands in facing Metalder on his own without the Neroz Army getting in the way.

Metalder decides to help Topgunder when he flees his execution for his failures in defeating the superhuman machine.

Tsurugi becomes a kid's soccer coach to discover the meaning of brotherhood as he becomes targeted by a brotherly duo of the Armor Corp.

When several members of Neros' army abduct a scientist associated with Tsurugi's creator, a member of the Armor Corps decides to help Metalder in exchange for a battle.

Ryusei tries to understand the concept of dreams as he's attacked by a member of the Monster Corp who forces him to have bizarre nightmares

Neros upgrades a violin-playing robot to become an unstoppable weapon who uses its music to lure and defeat Metalder.

A retired member of the Robot Corp tries to escape from Neros' services, only to be drawn back in to protect others due to his betrayal.

Metalder rescues a girl attacked by Neros' ninja squadron, unknowing of her own grudge against him from a fallen foe.

When a man unknowingly working for Neros runs away from one of his schemes, Metalder must help rescue him and his family from Violent Spirit Hidouman with some help from a familiar rival.

A girl captured to work as a slave for Neros becomes a warrior believing that defeating Metalder is the only way to save her sick little sister.

The son of Hedogross and Wisdom decides to become a member of the Neros army to honor his father, forcing his mother to enlist Metalder to not make the same mistake.

An aspiring biker ends up being pursued by a squad of Neros assassins aiming for Metalder. Will Metalder save the biker from a squad of Neros' assassins?

Topgunder returns to help Metalder deal with the assassin Crosslander; while Mai becomes captured by a revived Gamadone!

A troubled member of the Robot Army takes action when Mai gains access to secret information regarding Neroz's true identity.

A little girl who wanders into the Ghost Bank becomes assisted by Rhapsody as he protects her from Neros' forces. This is first time Metalder confronts God Neros on his headquarters.

When a family abandons a litter of puppies on a testing ground of Neros' Armament Army, a member decides to protect them from being attacked.

Hakko encounters a girl who sings to fireflies luring people to be utilized to have their cells taken for Neros' schemes.

Metalder becomes targeted by a squad of roller skaters hired by Neros to attack him in order to discover his weakness.

The four Neros squadrons compete against each other in a sports game while Metalder is lured by another member of the army into gaining a starring role in their affairs!

Ryusei must work with Princess Tenko in order to defeat a rival magician turned Neros warrior.

Ryusei protects a man who knows a secret of Neros while being assisted by an unlikely group of friends of Hakko.

With Hakko's life on the line, Tsurugi and the JAC squad must rush forth to save his life, determine an ally's trust, and defeat the plans of Victorious Saint Coolgin.

When an earthquake frees several of Neros' biological experiments, one ends up becoming friends with a young girl even as Ryusei and the emperor's forces search for them.

Metalder investigates a female thief who wishes to steal a gem from Neroz to fulfill a family promise.

A stray dog who befriends Metalder is taken away to be mutated into the latest member of Neros' Monster Army.

A boy who becomes lost in the woods becomes saved by Ryusei, as all of Neros' Robot Corp searches for his base.

A memoryless girl attaches herself to Ryusei as Neros puts a plan into motion to destroy Metalder mid-transformation.

Ryusei joins Mai on a journey to take a picture of a legendary flower, even as Geldring pursues it for his final chance to impress Neros.

Topgunder lays siege on Neros' forces, leading him into a siege where he becomes fated for a trap to execute him with Metalder!

Mai's father returns from America with vital information associated with Neros' true identity, even as he's targeted by an assassin.

Discovering a connection between Neroz and businessman Gozo Kirihara, Shingo Ogi decides to investigate, leading him into the underworld lord's trap.

Neroz hypnotizes Mai's father into destroying Metalder for him as Ryusei tries to save him and defeat the assault of the entire Robot Army.

Metalder and Topgunder head to the headquarters of the Ghost Bank in order to bring an end to the threat of Emperor Neros and his armies once and for all!

Seeking vengeance on Coolgin for the murder of Topgunder, Ryusei encounters another surviving general of the Neroz army seeking revenge while making a shocking revelation about the emperor's whereabouts.

Metalder confronts God Neros in a final showdown to bring an end to the evil overlord that may ultimately bring an end to the existence of the heroic superhuman machine.