The Shadow

"I need sleep."

- The Cosmic Entity The Cosmic Entity is a mysterious being who lives in and controls the Empty, a place of nothingness predating God, Death(presumably) and the Darkness.

Background
The entity controls the Empty and he explained to Castiel that the Empty existed before God or the Darkness. When angels and demons die, they go to the Empty where they eternally slumber, allowing the entity to do the same. If even one of its charges is awake, the entity is awoken as well until the awakened being is asleep again or out of the Empty.

Season 13
In The Big Empty, after the Seraph Castiel is awakened by Jack's telepathic call, the entity is awakened again. It arose in the form of a pool of dark liquid inside the Empty after Castiel walked by before taking on a vague humanoid form. As Castiel made his way through the Empty, he sensed the entity and called out to it. The entity took on Castiel's form to communicate with him directly, though it spoke with a distinct voice and accent. The entity identified itself as "just your friendly, neighborhood cosmic entity" and stated that it has taken on Castiel's form as its real form is too frightening.

The entity explained to Castiel that the Empty is what existed before everything, including God and the Darkness and Castiel was "soaking in it." The entity told Castiel about how every angel or demon that has ever died was in an eternal sleep inside the Empty and was confused by how Castiel was awake. According to the entity, "in all of forever", nothing has ever awakened inside the Empty. Castiel suggested that the Winchesters must have made a deal, but the entity stated that only it has power over the Empty with not even God having power there. The entity put its hand to Castiel's forehead and painfully went through his memories in an attempt to find out what could have woken up Castiel. Afterwards, the entity explained to Castiel, who remained in pain, what he did and that it wanted Castiel back to sleep. Castiel realized from the entity's description that having being awake was painful for the entity. This was confirmed by the entity, stating that if Castiel could not sleep, then the entity could not sleep as well.

The entity insisted that it likes and needs sleep, causing Castiel to suggest that it get rid of him by sending Castiel back to Earth. The entity suggested that it instead throw Castiel so deep into the Empty that he could not bother it anymore, but Castiel recognized that the entity was bluffing. Castiel challenged that the entity's plan would not work as the entity would have already done it. The entity acknowledged that Castiel is right, but refused to send him back, telling Castiel that "it's not part of the deal." The entity stated that it has gone through all of Castiel's mind and knew everything there about him and claimed that there was nothing back on Earth for Castiel. The entity grasped Castiel's head and painfully showed Castiel visions of his grace being stolen by Metatron, his death at the hands of Lucifer, the Escape of the Leviathans and Castiel returning the souls to Purgatory. The entity struck down Castiel, attempting to convince Castiel to return to sleep. However, Castiel refused the entity's demands and declared that no matter what the entity does, he will fight it for eternity if he was not released. The entity angrily denied Castiel's words as Castiel continued to demand his release.

Castiel later awakened in a meadow on Earth and realized that the entity has resurrected him as Castiel demanded.

Powers and Abilities
Being the supreme ruler of the Empty, the entity possesses immeasurable supernatural power, allowing it to do almost anything it wishes within its own realm.
 * Nigh-Omnipotence (within the Empty) - The Entity has the power to do practically anything and has complete control over the Empty. The entity claims that not even God has strings on the Empty and all within it. However, the entity lacks the ability to force something that has awakened in the Empty back to sleep and must either convince them to return to sleep on their own or expel them.
 * Nigh-Omniscience - It knows about the world and what happened before its creation however, even it couldn’t figure out why Castiel had awoke in what it considers all of forever.
 * Shapeshifting - Due to its true form being too terrifying or maddening for anything's eyes, the entity can take on the form of the being it is speaking to, though it speaks with a distinct voice instead of mimicking the being's voice.
 * Super Strength - The Entity was able to effortlessly overpower Castiel.
 * Telepathy - In order to learn more about Castiel, the entity painfully dug through his memories. The entity later used this power to show him some of his most painful memories in an effort to convince Castiel that he was worthless and should go back to sleep.
 * Resurrection - The entity was able to resurrect Castiel, returning him to Earth in the process.
 * Healing - Despite Castiel's vessel being burned and destroyed, the entity was able to restore it with no sign of damage.

Weaknesses
Although it is the ruler of the Empty, it has a few weaknesses as well.


 * Awakening of The Empty Inhabitants - As long as the inhabitants of the Empty sleep, so does the entity itself. However, if even a single inhabitant is awake, it also wakes up the entity from its sleep. Furthermore, having waking inhabitants in the Empty causes it pain.
 * Sleep Deprivation - Being in deep slumber since before all existence, the entity can be severely disturbed if it cannot rest. Castiel claimed, while he cannot beat the entity, he can stay awake to lay pressure to it.

Trivia

 * The Entity claimed that its true form induces complete insanity, even to angels.

Appearances

 * Season 13
 * The Big Empty