At Princess Sophia's behest, Makoto Takatsuki faces off against the lava giant that's incinerating the capital. Not even the city's best warriors stand a chance, but Makoto uses his Synchro skill to access Sophia's king rank ice magic and strike a decisive blow! Having saved the day, Makoto is rewarded with the "Hero" title he's always dreamed of. It feels good to finally be recognized for his efforts, but being a hero comes with new trials to face. At least Sophia's icy exterior is starting to crack—but little does he realize that he's melted her heart completely! Once things settle down, the party takes a well-earned holiday to the sunny beaches of the Habhain Islands. Everyone vies for Makoto's attention, but he's more concerned about uncovering the ancient secrets that lurk beneath the waves...