GARO: Heir to Steel Armor

Mutsugi plans to open the Gate of Destruction and drive out humans with Inga. Souma Shirahane, who has been engulfed in his soul's darkness by Mutsugi's trickery, loses his sanity and thrusts his sword into the Lost Soul Beast form of Godou Shirahane's Zango armor, which is the key to sealing the gate. Ryuga Dougai crosses swords in order to stop Souma from going out of control. On the other hand, Koyori stands up to Mutsugi even though she is conflicted. However, the seal of the Lost Soul Beast Zango is broken with each passing moment.

The Gate of Destruction, which has regained its original form, causes a "forbidden fruit" which bestowed omniscience and omnipotence before Mutsugi's eyes. She promptly consumed the "fruit", attaining power boost she sought yet corrupted her at the same time. Ryuga Dogai, Souma Shirahane, and Koyori stand against Mutsugi, who is trying to use a technique to purge humanity of their Inga. What is Inga? What is a human? The battle for the mission of the protector begins.

Mutsugi has been assimilated by the Seducer who aimed to plunge the human realm into chaos once more, becoming a Horror. Channeling her Inga, she altered Gate of Destruction into a more horrifying form. Golden Knight Garo and title-less knight Hagane, finally stand together to face a hopeless threat that will shake the world. Flash Sword Dance and Dark Flash Sword Dance - protectors, pass on the feelings you bet on Hagane to the future.