Item from Percy Jackson by Rick Riordan
Thalia's shield — a bracelet that expands into a terrifying shield bearing Medusa's face, causing supernatural fear in anyone who sees it.
Aegis is modeled after Athena's legendary shield (the original bore actual Medusa's severed head embedded in its face). In bracelet form it's a simple silver cuff on Thalia's wrist. Expanded, it becomes a large round shield embossed with a screaming Medusa face in Celestial bronze — and the face seems to move, writhing with serpentine fury. Enemies who look at it experience supernatural terror that overrides courage and combat training; monsters flinch and demigods stumble backward. Combined with Thalia's lightning powers and her natural ferocity, it makes her one of the most intimidating fighters alive.
In bracelet form: a silver cuff. Expanded: a large round shield embossed with a screaming Medusa face in Celestial bronze. The face seems to move — enemies who look at it experience supernatural terror and often run.
Also known as: Aegis, Thalia's shield