Dai, a young boy grew up in a peaceful island filled with monsters. He longs to be a hero and sees a group of people approaching the island by a ship. He is excited to meet another human being for the first time.
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. A Hero trainer arrives to inform Dai that the Dark Lord has returned. To save those he cares about, Dai undergoes Hero training.
Avan turned into a dragon and attacks Dai. Dai fights back to no avail. To defeat Avan's flames requires Wave Slash. As Dai clears his objective, someone enters the island. Who should appear before Avan but the worst possible being..
Thanks to Maam's help, Dai goes on the offensive against Crocodine. Popp joins in and the battle intensifies. Seeing Dai and Popp fight, Maam remembers Avan's words to her when she was young and comes to a decision.
Dai and company arrive late at night to the castle town of Romos. The next morning, Crocodine attacks with the Furfang Legion. In Romos Castle, Dai faces Crocodine. Crocodine decides to use the weapon that Zaboera gave him.
