4 — : Mermaid: The Girl Of Water City

: Unlike typical hostile monsters, Marie is friendly and aids Bell by healing his wounds using her blood and guiding him through the labyrinthine waterways.

: The "Water City" setting introduces a shift in tone, utilizing the claustrophobic and unpredictable nature of the underwater environment to heighten the stakes. 4 : Mermaid: The Girl of Water City

Watch the official trailer for the fourth season of the series here: : Unlike typical hostile monsters, Marie is friendly

: The episode highlights the growing danger of a "Moss Huge" monster, which demonstrates unusual intelligence by using parasitic spores to weaken adventurers and feeding on magic stones to evolve. : Marie provides Bell with critical information about

: Marie provides Bell with critical information about the Dungeon's layout and the monster's habits, establishing a bond that is vital for the party's survival in the subsequent battles. Key Themes and Development

: The episode serves as a precursor to the "Labyrinth Arc" climax, showcasing Bell's increasing maturity and his ability to trust and collaborate with non-human allies even in life-threatening situations.