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Nightmares are a new type of monster introduced in Rebellion. They resemble dolls with a pair of disembodied blue hands, and primarily attack by shooting exploding objects.

It is later revealed in the movie that the nightmares are actually false opponents created by the witch barrier Rebellion takes place in.

Appearances

At the moment, Nightmares exclusively appear in Rebellion.

Two nightmares appear in the movie. The first appears at the very beginning and is initially attacked by Madoka Kaname, Sayaka Miki, and Kyoko Sakura. The nightmare is driven into a dining room where Mami Tomoe and Bebe are waiting. The magical girls then appear to defeat the nightmare by feeding food to it. It's later revealed that Homura Akemi had assisted the magical girls in secret.

The second nightmare is born from Hitomi Shizuki, when she feels frustration over her relationship with Kyosuke Kamijo. Hitomi is seemingly swallowed up by her bed as the nightmare appears. The magical girls contain the nightmare and then defeat it by singing the Cake Song. At the end of the song, the nightmare turns into a cake which Bebe swallows whole. Bebe then spits out a blob resembling Hitomi's head and a paper with a picture of a violin on it. Sayaka catches both things, and then throws the paper into the air. The paper turns into a silhouette of Kyosuke playing the violin. The blob flies up after the silhouette and vanishes into sparkles that purify the magical girls' soul gems. Hitomi then reappears in her bedroom.

It is eventually revealed that the characters are actually in Homura's witch barrier. The nightmares were created by the Homura's subconscious so the magical girls would have enemies to fight.

Later in the movie, a nightmare doll is seen briefly as Kyubey explains Homura's circumstances. Another appears briefly when Homura transforms into Homulilly.

In the 6th anniversary of Magia Record, they were introduced as enemies to defeat with the introduction of Devil Homura as a playable character. It was revealed that both of the nightmare had names, written with a new type of runes, along side their own descriptions.

Observations

The disembodied hands of the nightmares hint at the fact that they're puppets created by a witch. Furthermore, one of the hands has a covering over it's middle finger, which is the same finger a magical girl wears her ring on.
Note how the dots on the hands resemble the ones that appear on Homura when she starts to discover she might be a witch.
A mare or nightmare (Proto-Germanic: *marōn; Old English: mære; Old Norse: mara; German: Nachtmahr) is an evil spirit or goblin in Germanic folklore which rides on people's chests while they sleep, bringing on bad dreams (or "nightmares"). The mare is often similar to the mythical creatures succubus and incubus, and was likely inspired by sleep paralysis.
It is interesting to note that mara, besides being a root-word for nightmare, is also the name of a Buddhist deity analogous to the devil. Although this may be a coincidence, Homura does ascend to become a Mara-like figure at the end of Rebellion.
Their connection with Homulilly was hinted on their tags, which reveals stylised runes of Homulilly's name. While it was hard to see during the movie as they were constantly moving, the tag is much easier to observe in Magia Record.
- Judging their role as false enemies inside the fake Mitakihara Town (Homulilly's barrier), it is suspected that Nightmares might be also a type of her Familiars.

Powers and Abilities

It is unknown if both Nightmare's share the exact same powers as one another, but both of their powers are themed after stuffed objects. Fitting for their dream themes.
- The first Nightmare, Kuma no ko no yume, has the power to shoot incredibly destructive pillows and teddy-bears that have been able to destroy entire buildings. It also has the power to summon dancer figures and uses bubbles to attack.
- The second Nightmare, Yagi no ko no yume, has the power to turn any object into a stuffed version of itself, then blow it up with teddy-goats. It also attacks using music instruments, mainly violins.

Descriptions

くまのこのゆめこの夜のすみっこで　ひとりぼっちの子がみた　さびしい夢。はらぺこなお腹にやわらかな綿を詰め込んで今夜はすきなだけ　わがままに振る舞いましょう。踊り子たちだけが　あなたを知っています。

Kuma no Kono Yume
Runes
Type	Little Bear's Dream
Episodes	The Rebellion Story

“A poor, tearful dream that a lonely girl saw in a corner of this night. Fill your empty belly with soft cotton stuffing, and dance around selfishly as much as you like tonight. The dancers alone know who you are.”

やぎのこのゆめこの夜のすみっこで　心優しい子がみた　かなしい夢。自己嫌悪で濡れた枕の中身を大きな頭に詰め込んで今夜はすきなだけ　泣き喚きましょう。踊り子たちだけが　あなたの手を取ります。

Yagi no Kono Yume
Runes
Type	Little Goat's Dream
Episodes	The Rebellion Story

“A poor, sad dream that a gentle-hearted girl saw in a corner of this night. Fill your big head with the stuffing of your pillow, wet with self-loathing, and cry and wail as much as you like tonight. The dancers alone will take your hand.”

Trivia

The first Nightmare seems to enjoy food a lot as shown in the movie and concept art.

Gallery

Official Art

The first Nightmare from the Rebellion Material Book
Art from the Rebellion Production Note which shows the Nightmare's appearance in reflections
Art of Hitomi's Nightmare and the first Nightmare
An unused Homura Nightmare
Concept Art showing the storyboard for Mada Dame Yo