Amplifier is a tall woman with short honey brown hair, reaching just past her chin, and matching eyes.
Her hero costume consists of a pale pink cropped shirt with a short, puffed sleeves, a high collar and a darker hem, which is left open to reveal the tight navy blue cropped top she wears. She also sports a pink miniskirt with a white and black pattern along the hem and sides, dark purple shorts, a belt with a large, oval-shaped buckle and a headset with a microphone over her cheek, as well as a pink star painted below her left eye.
Amplifier runs the "Villain Attack" attraction for the I-Expo's Early Access Event. She praises U.A. Students Eijiro Kirishima and Katsuki for their high scores.
Izuku Midoriya goes next and scores second place behind Katsuki. Then Shoto Todoroki beats all of their scores, surprising Amplifier the most. She tries to move on to the next contestant, but Katsuki's rage silences her as he makes a scene over Shoto's score. 
Yell (エール Ēru?): This Quirk allows Amplifier to project her voice to multiple spots at once, imitating surround sound speakers.