Valkyrie Drive: Mermaid (2015)

S1E8 Valkyrie Effect

Akira enlists Lady Lady to explore a site rumored to hold the secrets of Mermaid, bringing along Mamori, Mirei, and Meifon. Inside a concealed cave, they stumble upon an underground manufacturing facility, where they are ambushed by a familiar-looking Artificial Arm. Struggling to cope with the aftermath of her earlier assault, Mamori is unable to assist, prompting Mirei to tap into her latent powers to confront the Arm, though she is still overmatched. In a moment of determination, Mamori activates her own enhanced abilities, transforming into a powerful arm that allows Mirei to triumph. As the facility collapses around them, the battle’s energy attracts the attention of another island, prompting the arrival of Momoka Sagara to investigate.