Dormammu (Marvel Cinematic Universe)

"You've come to die! Your world is now my world, like all worlds!"

- Dormammu welcomes Strange in the Dark Dimension

Dormammu is the Bigger Bad of the 2016 Marvel Cinematic Universe movie Doctor Strange. He is a gigantic, godlike force of pure evil who exists in the Dark Dimension and seeks to spread his malign influence to all other worlds. He is the MCU's adaptation of the comic villain with the same name.

He was played by Benedict Cumberbatch (who also plays Doctor Strange) via motion capture, with his voice being a blend of Cumberbatch's and an also uncredited unknown actor's. Cumberbatch also portrayed Smaug and Sauron in the Hobbit film trilogy, Khan from Star Trek: Into Darkness, William Prince Ford from 12 Years a Slave, Julian Assange from the Fifth Estate, and Alan Turing from The Imitation Game.

History
Dormammu is a resident of the Dark Dimension and wishes to merge all existing universes with it. Despite his sinister plans, a group of Zealots mistakenly believes that Dormammu should be allowed to merge Earth with the Dark Dimension, believing that this would eradicate time and death and would thus grant eternal life. The Zealots, led by Kaecilius, contact Dormammu who grants them strength through the powers of the Dark Dimension. He tasks Kaecilius with destroying the sanctums of magic in Hong Kong, London and New York to allow Dormammu to spread the Dark Dimension on Earth. Kaecilius succeeds to destroy the three Sanctums, creating a portal in Hong Kong through which Dormammu spreads the Dark Dimension on Earth.

However, Dr. Stephen Strange (a new member of the Masters of the Mystic Arts) reversed the time by the use of the Eye of Agamotto and the Infinity Stone inside it to undo the sanctum's destruction, and then flew into his dimension to negotiate with him. Dormammu immediately refused and quickly killed Strange by blasting him with energy, but to his confusion, Strange reappeared on the Dark Dimension surface, repeating himself confidently.

Perplexed, Dormammu killed Strange again, only to have him reappear again, repeating his intention. Stunned, Dormammu demanded to know what was happening; the Doctor then revealed that he had used the Eye of Agamotto and the Infinity Stone inside it to create an infinite time loop, with them spending eternity together in a endless cycle, the only trap Dormammu could not escape from since the Dark Dimension was a place beyond time itself and therefore Dormammu had no power over it. Eventually, after killing Doctor Strange multiple times, Dormammu began begging him to end the time loop, which he did, on the condition that Dormammu banished himself and the Zealots from Earth forever. Dormammu reluctantly did this, while also turning the Zealots and Kaecilius into Mindless Ones and dragging them into the Dark Dimension forever, and kept his own word, sealing the portal between the dimensions.

Personality
Dormammu appears to be a being of pure and utter malevolence, seemingly focused only on expanding his Dark Dimension realm and conquering all other worlds and dimensions of the Multiverse, in order to fuse them in as well.

Powers

 * Mystical Entity Physiology:  Dormammu is an entity comprised of eldritch mystical energies. His position as the absolute monarch of the Dark Dimension also gives him further increased mystical power.
 * Immortality: Being beyond time itself, he is an immortal. It is unknown if he can actually be destroyed.
 * Power Bestowal: Dormammu can bestowed anyone whom directly contact him powers. Powers that Dormammu bestowed are Immortality, which allowed to live forever; Reality Warping, ability to warp and twist the landscape of area around user, without being inside of Mirror Dimension, run on walls and ceilings while completely disregarding gravity, and enhanced one' momentum to the point where he could easily send someone flying with one's attacks even while defying gravity; and Space Shard construction, ability to shape space around user into glass-like material that also can be formed into weapons. However, it comes at the terrible price that Doctor Strange later revealed: The bestowed powers would established a bond between Dormammu himself and those whom gained the said powers, allowed him to absorb them into his Dark Dimension at will, causing them to rapidly turn into decayed, fossil like figures with glowing red symbols of the Dark Dimension on their heads. He bestowed them to Kaecilius and the Zealots in order for them to challenge the strength of the Ancient One.
 * Energy Projection:  Dormammu can project powerful energy blast from his mouth, these energy blast are strong enough to kill humans immediately.
 * Dimensional Lordship: Being the absolute monarch of the Dark Dimension, he has complete molecular control over the entire dimension.
 * Reality Warping: He has absolute control over the Dark Dimension, likely due to being the absolute monarch of the Dark Dimension.

Trivia

 * Rather than being wreathed in flame like in the comics, Dormammu appears to be a being of pure shadow and darkness but with bright purple eyes, although he does appear to have red "shadows" surrounding his entire body - this may in fact represent the "flames".
 * Despite being by far the most powerful villain in the movie (and possibly the strongest character in the entire Marvel Cinematic Universe), Dormammu is listed as a secondary character because he has far less screen time than Kaecilius, making him the Bigger Bad instead of the Big Bad.
 * It was Benedict Cumberbatch's idea to perform motion-capture for Dormammu, as he felt that the character should be an evil reflection of Doctor Strange.
 * In-universe, Dormammu's physical resemblance to Strange is a form Dormammu assumed to mock Strange.
 * This incarnation of Dormammu resembles Thanos.