Dream Eater

The Dream Eaters (ドリームイーター) are a species of creature in Kingdom Hearts 3D: Dream Drop Distance. As their name suggests, they reside in the Realm of Sleep, where they consume dreams. Dream Eaters fall under two major categories, Nightmares (ナイトメア), which eat good dreams and plant bad ones, and Spirits (スピリット), which only eat bad dreams. Nightmare Dream Eaters serve as the primary enemies, while Spirits serve as recruitable allies that Sora and Riku can collect.

Story
Following Ansem's defeat at Sora's hands, a portion of the worlds attacked by the Heartless remain submerged in sleep. Yen Sid explains that though this means the Heartless cannot reach them, they are instead plagued by Dream Eaters, entities produced by the darkness present in these specific worlds and who seek the worlds' Keyholes. Two kinds of Dream Eaters are produced: benevolent Spirits and malevolent Nightmares, constantly in conflict with each other.

As part of their Mark of Mastery exam, Sora and Riku journey into the Sleeping Worlds to awaken them, in the process recruiting several Spirits to help them in their quest and battling and destroying Nightmares.

Shortly after Sora first meets Neku, the two of them are surrounded by Dream Eaters. Neku summons his own Dream Eater, a Necho Cat. It is then that Neku convinces Sora to partner with the Dream Eaters. Later, Beat summons a Kooma Panda to encounter Riku.

When Sora and Riku return to Traverse Town, they find that their companions have abandoned using Dream Eaters, and have instead simply banded together with their partners. They also find out that a powerful Nightmare, the Spellican, has been wreaking havoc on the city, and that the participants in the Reaper's Game are tasked with eliminating it. Sora and Riku manage to corner the Nightmare, but it summons several other powerful Nightmares as a diversion, allowing it to escape.

Eventually, Mickey's actions in Symphony of Sorcery accidentally summon the Spellican, who takes control of Mickey and forces him to continually conduct music, causing chaos. However, Sora, with Riku's help, manages to reach the Spellican and defeat him.

Riku eventually makes his way to The World that Never Was, and finds himself face to face with Ansem, who reveals that Riku himself was acting as a Dream Eater within Sora's dreams throughout the entire time in the Realm of Sleep. Riku was fighting the Nightmares that were trying to reach Sora and his heart, but ultimately he had failed, as Organization XIII had managed to force Sora into a deep sleep.

After defeating Ansem and escaping to the real The World that Never Was, Riku finds himself at a dead end, unable to reach the Castle that Never Was, where Sora is trapped. He soon notices a Meow Wow at the entrance to the castle, however, and uses the power of his own Komory Bat to forge a link between the Spirits and ride a Dreamline to the castle.

Following Xehanort's defeat at Riku's hands and the end of the exam, Sora decides to visit Traverse Town, and is reunited with all of his Spirit friends, having given them access to the Realm of Light as he had hoped.

Design
Like the Heartless, Nobodies and Unversed before them, the Dream Eaters come in a variety of sizes and shapes, although they appear to have a much higher range of color schemes than their predecessors, and often resemble animals. Each Dream Eater is adorned with an emblem which signifies whether it is a Spirit or Nightmare.

Dream Eaters are characterized by having colorful appearances. Nightmares tend to have darker color schemes, while Spirits have lighter, pastel colorations. Nightmares also tend to have round, red eyes which lack pupils, while those of Spirits are either yellow, blue, green or purple. A Spirit's eyes change color as its Disposition changes.

The symbol of the Spirit Dream Eater is present on the back of Riku's third outfit to symbolize his presence inside Sora's dreams, acting like a Dream Eater by vanquishing Nightmares, while the symbol of the Nightmare Dream Eater appears on the visor of Ventus's Keyblade Armor when it is possessed by a Nightmare with Sora inside it.

Nature
Dream Eaters exist only within the Realm of Sleep, feeding on the dreams and nightmares of those who sleep. The Nightmare Dream Eaters largely outnumber the Spirits, who only appear in small numbers to assist Sora and Riku.

Dream Eaters react to various forms of treatment, appearing to be happy when they are shown affection. Dream Eaters are able to share power with one another and with other beings in a variety of ways. Sora can utilize his companions in a combination attack, while Riku is able to harness their power to perform stronger attacks.

Spirit Dream Eaters have various Dispositions; each Dream Eater has different ones. These Dispositions can be altered by boosting Affinity with the Spirits. When a Dream Eater's Disposition changes, its eyes change color, and a new path may be formed on its Ability Link board.