Day Dream

Set down in Japanese as Burein Rimōdo, literally "Brain Remode", this Emitter Quirk has a range that varies with circumstance and reaches audiences through the fourth film, My Hero Academia: You're Next.

Line of sight is the only trigger. Once Deborah locks onto someone by eye, they either collapse unconscious or fall into a hypnotic state she can steer for a short while, their mind marooned in a dream world built from their deepest desires and their body left close to comatose. The victim's eyes wash out to pure white, and her own glow red, the way Shota Aizawa's do under Erasure.

The vantage runs both directions. Deborah can look in on what her targets are dreaming, which is how she pulled Giulio Gandini's history as Anna Scervino's butler out of his fantasy. Ordinarily a single victim is her ceiling, but with her Quirk Factor amplified by Overmodification the ceiling all but disappears and she can take a near endless crowd.

The constraints follow from the trigger. She must see her target, and without a boost she is limited to a single victim. Overmodification lifts that cap to large numbers at once.

Her own body is the weak link. A serious injury to Deborah in the waking world releases everyone she has under, which makes her a target worth reaching. Victims also have a route out from the inside: someone else can make them aware the fantasy is false, after which they regain limited command of their real body.

A borrowed consciousness defeats it outright. Any additional personality living inside the affected person goes untouched and can break the host loose, which is what the One For All Vestiges did for Izuku Midoriya, freeing him to move through the psychosomatic world at will. Artificial parts are similarly exempt: Giulio's robotic eye recognised Deborah and fired his prosthetics into an attack while the rest of him was still under.

Deborah Gollini is the only holder, and control rather than combat is the point. Keeping victims pacified stops them running, which is how she held Anna docile so the Gollini Family could go on exploiting her Overmodification. She later swept the captives aboard the family's flying fortress, intending to run these specimens through Overmodification and field them as living weapons, though only a handful proved compatible with Anna's power. Class 1-A and Giulio went under the same way, each one parked inside their own wish.

Those wishes are the film's real inventory. Shoto Todoroki is a child again playing soccer with Toya, Fuyumi, and Natsuo while his parents watch happily. Tenya Ida works as one of the Ingenium Brothers beside a Tensei who never lost the use of his legs. Izuku is small again in an All Might-stuffed bedroom, adventuring with the man himself. Mezo Shoji stands unmasked and accepted in his hometown. Kyoka Jiro plays guitar on a stage, Momo Yaoyorozu takes tea at the family mansion, Tsuyu Asui sings with her family over a frog pond in the rain, Ochaco Uraraka sleeps on a mountain of mochi, Toru Hagakure is visible and trying on clothes, Mashirao Ojiro cuts a striking figure in black leather and yellow shades, Hanta Sero surveys the city on his Tape, Minoru Mineta and Denki Kaminari share a beach harem, and Giulio simply tends to Anna inside the Scervino mansion.

Brainwashing makes the obvious comparison, since both park a target in a controllable trance, but the entry points differ: Day Dream needs sight, Brainwashing needs conversation, and Brainwashing's victims will follow a broader set of orders. Pain undoes Brainwashing while injury to the caster undoes Day Dream, and in both cases the One For All Vestiges gave Izuku an exit nobody else had.