Stephen Strange

Stephen Strange, an arrogant neurosurgeon, destroys his hands in a car crash and exhausts every medical option before finding Kamar-Taj in Nepal. Strange becomes Master of the New York Sanctum. Strange puts himself in a time loop using the Eye of Agamotto and confronts Dormammu inside the Dark Dimension.

One scene: he holds Loki in a falling loop, and sends the brothers on to Odin in Norway.

Sequence of acquisitions: Power (Xandar — the attack on the Nova Corps happens entirely offscreen between films, acknowledged only in a passing news report), Space (Loki), Reality (from the Collector, in a trap), Soul (Vormir — the Stone requires the sacrifice of someone you love, so Thanos throws Gamora off a cliff), Time (Strange gives it to him voluntarily to save Stark's life), Mind (torn from Vision's head). Strange, who spent the film insisting he'd let both Stark and Parker die first, hands over the Stone. Strange looked forward through 14,000,605 possible futures and found exactly one where they win.

Back through his own portal, and the reason everyone else comes through theirs — he is the one who saw which ending works.

He asks Doctor Strange to make the world forget he's Spider-Man. Strange eventually contains it, but by then the spell has already started reaching into other universes for anyone who knows that Peter Parker is Spider-Man. On Strange being able to cast something this powerful: he explicitly says he shouldn't, and Wong tells him not to.

Strange takes America to Earth-838, where he meets the Illuminati: Mordo, Peggy Carter as Captain Carter, Blackagar Boltagon (Black Bolt), Maria Rambeau as Captain Marvel, Reed Richards (John Krasinski), and Professor Charles Xavier — Patrick Stewart, in the animated-series wheelchair. Wanda kills all of them.