The episode begins with a tense situation as Cassandra attempts to heal Chigusa and Luvis, who are infected by a parasitic plant. Despite her efforts, the plant proves beyond her healing abilities, and cutting it off only worsens the situation. As the scenario grows increasingly urgent, Bell encourages the group to brainstorm solutions.

Two options emerge: retreating to the surface to seek help from a more powerful healer or directly confronting the enhanced monster responsible for the disease. The group opts for the latter, hoping that defeating the monster will also cure their afflicted comrades.

The narrative shifts to the strategic engagement with the enemy. Lili, acting as the tactician, assigns roles to the group members. Bell and Asha are tasked with confronting the Moss Huge, the central antagonist. However, the Moss Huge cleverly positions the weaker group members near itself, forcing Bell to intervene protectively.

During the confrontation, Bell's Firebolt attack provokes a reaction from the Moss Huge, which captures him and throws him into the water. Bell's situation becomes dire as he nearly runs out of air but is unexpectedly freed and hurled over a high waterfall, separating him from the group.

In Bell's absence, Lili struggles to maintain composure but is reminded by Aisha of her responsibility as the tactician. A new plan is devised: lure the Moss Huge to a strategically advantageous location and trap it using Makoto's gravity magic.

Meanwhile, Bell, having survived the fall, faces a new threat—the Iguazu. Remembering Ais's techniques, he resolves to confront the Iguazu head-on. Despite his injuries, he manages to repel the creature.

The episode ends with the injured but victorious Bell receiving unexpected applause from a mermaid who had been observing him.