Rewind

Read as Maki Modoshi, Rewind is the close-range Emitter ability belonging to Eri, debuting in Chapter 156 and Episode 76. It reverses a living being's body to an earlier physical state, and it leaves its owner with a small brown horn above the right brow that swells whenever the power engages. Nothing on either side of Eri's lineage resembles it, marking the Quirk as an extremely rare mutation.

Activation makes the horn grow and shine brightly. Anyone touching Eri or standing near her at that moment begins reverting, with injuries and alterations undone or restored depending on how far the process reaches. Carried far enough, a target can be pushed to a point before they existed and simply erased. Kai Chisaki, who called the ability terrifying, claimed it can rewind genetics themselves.

Emotion feeds it. As the Shie Hassaikai Raid reached its climax, Eri's memory of Mirio Togata risking everything for her turned into resolve, and the Quirk fired on its own, unwinding Kai after he had fused himself with Shin Nemoto. With Izuku Midoriya shielding her, the effect kept intensifying, and he rode it to sustain Full Cowl at one hundred percent. Afterward the power ran wild until Eraser Head shut it down and her horn shrank back to a stub.

The limits are severe. Rewind touches only living things, which made safe practice nearly impossible until Eri was placed with Eraser Head, whose Erasure could cancel it in an emergency. It demands direct contact or close proximity. Neito Monoma confirmed that it also depends on some unidentified energy accumulating first; without a reserve the Quirk lies dormant and the horn stays stubby, and each use spends the stockpile again. As a child Eri could neither understand nor control it, and her first manifestation rewound her father out of existence while he held her.

Eri is the sole holder, though her biology has been weaponized by others. The Shie Hassaikai built the Quirk-Destroying Drug out of her blood, cells, and flesh, tuning it to rewind a target's Quirk Factor into a Quirkless state, and they produced an antidote that was never recovered. Kyudai Garaki later reverse-engineered the formula toward Rewind's own effects, giving All For One a single-use dose during the Final War that repaired his fatal wounds and returned his body to its prime, with the acknowledged catch that nothing could keep it from erasing him eventually.

Eri's control improved through practice at regrowing severed limbs on insects and lizards, enough to restore Mirio Togata's Permeation after a Quirk-Destroying Bullet erased it. She lacked the stored energy to mend Eraser Head's injuries after the Paranormal Liberation War, but during Izuku's final battle she cut her horn off entirely and handed it over, letting Eraser Head rewind two or three minutes and regrow Izuku's destroyed arms. Eight years on the horn has grown back, though whether losing it damaged her power temporarily or permanently remains unknown.