Young Dai lives on Dermline Island, where he dreams of being a Hero. One day, a Hero and his companions come to the island. Dai is excited at first, but their true intent is to steal his best friend, Gomechan, the mythical Golden Metal Slime.
Dai must take Leona to the Earth Cave for a ritual. At first, Dai dislikes Leona, but they slowly come to understand each other. Suddenly, a giant Evil Scorpion attacks. Dai defeats it, but Leona is poisoned. As Dai’s wishes to save her...
A dark power affects Dai’s monster friends, driving them berserk. Brass tries to get Dai to leave. As they argue, a Hero trainer arrives to inform Dai that the Dark Lord has returned. To save those he cares about, Dai undergoes Hero training.
While Avan and Dai train, someone enters the island. Who should appear before Avan but the worst possible being...!
Avan is overpowered by Hadlar, who is now stronger than ever. To protect his students and the world, Avan gathers the last of his strength and faces Hadlar. Dai can do nothing but watch. Finally, the showdown between Avan and Hadlar is concluded.
CROCODINE, THE BEAST KING
Atsumi Tanezaki
Dai
Toshiyuki Toyonaga
Popp
Mikako Komatsu
Maam
Yuki Kaji
Hyunckel
Saori Hayami
Leona
