Thanos

"I know what it’s like to lose. To feel so desperately that you’re right, yet to fail nonetheless. It’s frightening, turns the legs to jelly. I ask you to what end? Dread it, run from it, destiny arrives all the same. And now, it’s here. Or should I say, I am."

- Thanos

Thanos is a fictional supervillain from Marvel Comics and the main antagonist of the Marvel Cinematic Universe. Thanos first debuted in a brief appearance during the closing credits scene of the 2012 Marvel film The Avengers before being formally introduced in Guardians of the Galaxy.

Thanos was created by Jim Starlin and Mike Friedrich.

Background
Thanos was born millions of millions of years ago on planet Titan, as belonging to the humanoid race known as Titans. Among his race, Thanos was born with physical deformities that he was considered an outcast. Despite this treatment, Thanos cared about his race and tried to save it when he discovered that Titan was reaching overpopulation. He suggested culling numbers by eliminating half the population, but his idea was considered too drastic and rejected by the Titans. Ultimately, Titan was so devastated by internal conflict and resource exhaustion that the race became extinct.

After the fall of Titan, Thanos made it his life goal to balance the universe by wiping out half of all life. He earned such a fearful reputation that he became considered as among the most, if not the most, powerful and influential warlord in the galaxy, ruling over a distinct region of space, having gained control over the deadly armies of the Chitauri and Outriders. He also collected and trained orphans from the species he balanced to become loyal liutenants and they eventually considered him their father, although he felt no affection for them.

When balancing Zen-Whoberi, Thanos's attention was caught by a young Zehoberei named Gamora. Impressed by how she fought off one of his guards, Thanos took her aside and distracted her with a knive while his army massacred half of the Zehobereis. He then adopted her and grew to genuinely care for her unlike his other children.

Thanos also massacred the Luphomoids and adopted Nebula. Thanos was known for being very cruel to her for being weaker than Gamora and always removed and replaced a part of her body with machinery whenever she lost.

Thanos eventually realized there were far too many lifeforms on the universe for him to balance them all and he realized that the Infinity Stones, objects of immense power that held considerable dominance over the various forces that occupied the universe, can overcome this and forged several alliances in order to locate them. He successfully located at least one of the stones; the Mind Stone, which he then hid inside a Scepter that was capable of manipulating minds.

Through many years of searching, Thanos discovered a lead on the Orb's location, sending Nebula and Gamora to the Cloud Tombs of Praxius under the command of his ally, the Kree soldier Korath the Pursuer. Nebula fell victim to a trap during the mission, and Thanos, not one to tolerate failure, forbade Gamora from rescuing her. Nebula was forced to amputate her own arm in order to escape. The Orb was never recovered, but Thanos let the failure pass and resumed his search. Thanos also send Gamora and Nebula to find the Soul Stone but Gamora reported to him that she was unsuccessful. Thanos, being as perceptive as ever, was easily able to see through the charade but let her believe that he was fooled.

Marvel Cinematic Universe
Thanos was a native of the world Titan, a prosperous and highly developed world. Despite this, Thanos had made notice that like many other worlds, Titan suffered from overpopulation, and due to limited natural resources, he forsaw that this would lead to Titan's destruction. He offered a macabre solution to the leaders: to kill half of Titan's populace, therefore ensuring that the survivors would persevere. His methods were deemed evil and he was deemed a madman, and thus

The Avengers
The Other tells Thanos that the Tesseract is on a small world, a human world. It also informs him that Loki is ready to lead the Chitauri. In a post-credits scene, Thanos is revealed to have been Loki's benefactor, having provided the Chitauri army used by Loki in his attempted invasion of Earth. When advised by his intermediary (known simply as the "Other" ) that opposing the Avengers would be "to court death", Thanos glances at the camera and flashes an evil grin.

Guardians of the Galaxy
Thanos plays a more active role in the film, where he has enlisted the help of Ronan, Korath, and his daughters, Gamora and Nebula, to retrieve the Orb for him. As it turns out, Gamora is not actually Thanos daughter, since Thanos killed Gamora's family and snatched her as an infant to train her into the perfect assassin, having abused and tormented her in the process of doing so. This causes Gamora to betray Thanos, which leads to a chain of events that leads to Gamora finding her true calling as a protector of the universe and a member of the Guardians of the Galaxy.

When Ronan and Nebula are called to discuss Gamora's betrayal, Ronan kills The Other, who was speaking for Thanos. Thanos does not react to this but is angry at Ronan for not obtaining the Orb (and for apparently alienating Gamora). He says he will destroy Xandar for Ronan if he brings him the Orb, but furiously promises that if Ronan fails again, he will ''Bathe the starways in your blood."

Thanos promised Ronan that he will help Ronan destroy Xandar in exchange for Ronan's services. However, once Ronan gets ahold of the Orb, he feels he no longer needs Thanos help and also decides to betray him. Nebula also decides to betray Thanos out of jealousy over Thanos showing preference for Gamora over her. Ronan and Nebula take Korath with them. In the end, Ronan and Korath are killed by the Guardians of the Galaxy (including Gamora), Nebula escapes and becomes a renegade villain independent of Thanos, and the Guardians give the Orb to the Nova Corps for safekeeping.

Thanos, however, is still determined to find the six Infinity Stones and the Infinity Gauntlet so he can use them to conquer the universe.

Avengers: Age of Ultron
In the mid-credits scene, Thanos retrieves the Infinity Gauntlet from a vault and heads off in search of the Infinity Stones himself after the failings of Loki and Ronan the Accuser.

Avengers: Infinity War
Thanos directly serves as the main antagonist of this film, having finally collected all Infinity Stones, and combating against the reformed and expanded Avengers, allied with the Guardians of the Galaxy.

Avengers 4
Thanos will return as the antagonist of the 2019 sequel Avengers 4, continuing and concluding the story arc of Infinity War.

Avengers Assemble
At the end of Season 1 finale The Final Showdown, Thanos is revealed to be Red Skull's master as Red Skull gives him the Tesseract. In the final moments of the episode The Arsenal, Thanos comes to Earth in search of the Power Stone.

In Season 2, Thanos is the overarching primary antagonist, sharing the role with Ultron and the Squadron Supreme.

In Thanos Rising, after attacking the headquarters of Uatu, Thanos shoots down an Avengers Quinjet. After falling into a trap of the Avengers, Thanos confronts the Avengers, Thanos wins easily but Arsenal hits him with the power of the Power Stone. However, Thanos reveals that is in possession of the Infinity Gauntlet and takes the stone from Arsenal.

The Avengers manage to belay Thanos, who is defeated when Arsenal unleashes the power absorbed by the stone, blasting Thanos halfway across the galaxy.

At the end of Widow's Run, after a debacle with Dormammu and Black Widow with the Infinity Stones, Thanos finally returns to Earth at the last minute, and claims the Stones, assembling them into the Infinity Gauntlet. Retreating into space, the Avengers pursue him. In Thanos Triumphant, Thanos begins to use the Stones to construct a shrine for himself above the Earth, and with a wave of his hand, wipes out dozens of stars. However, the Avengers, using Titan technology, charge towards him. While using Titan battle suits, the Avengers are no match for the Infinity Gauntlet's power. Thanos effortlessly trashes the mechs, and the Avengers take him head-on.

Trivia

 * Although being the main antagonist of Avengers: Infinity War, Kevin Feige described him as essentially being the main character as he will have a major role and it will explain his motivations for his actions.
 * Actor Damion Poitier portrayed Thanos only in The Avengers. Josh Brolin portrays Thanos in subsequent films via motion-capture and vocal performances.
 * Thanos name is derived from, the Greek personification of death.
 * Thanos made an appearance in the video game Fortnite as a playable character for a limited time, part of the Avengers: Infinity War movie promotion.