Attack On Titan The Shadow Beneath Me

Analise Goldschmidt always had a goal: hiding her identity, whether she had to kill, or pry herself into the smallest crevice. After a terrifying experience, she joins the 104th trainees squad to hone her skills to fight and become brutal. When an accident occurs, she reveals something that is almost indestructible. Is humanity facing something more or less terrifying than the Titans?