Avengers: Infinity War

Thanos, with the Black Order, collects the Stones. He already has Power (taken from Xandar, offscreen). He takes Space from Loki — and kills Loki, and Heimdall. Thor is left drifting; Hulk is beaten so badly that Banner cannot summon him again for the rest of the film.

Loki was never truly on Thanos's side — coerced, not allied. The Avengers shows him visibly unwell and under pressure; Infinity War confirms it when Thanos reminds him he was given an army and a Stone and failed.

He also genuinely wanted to rule Earth. Both are true — that's the character.

Heimdall dies here, permanently, immediately after using the last of his strength to send Hulk to Earth as a warning. He has not returned, and Idris Elba is not on the Doomsday cast list.

The Black Order — Thanos's four adopted enforcers, also called the Children of Thanos. Ebony Maw (telekinesis and manipulation; blown into space by Stark and Parker), Corvus Glaive (killed by Vision), Proxima Midnight (killed by Wanda), Cull Obsidian (killed in Wakanda). All four dead by the end of the film; the 2014 versions return briefly in Endgame and die again.

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).

Vision spends the film begging Wanda to destroy the Stone in his forehead, arguing one life against half the universe. She refuses until the last possible second, then holds off the entire battle with one hand while destroying the Stone — and Vision — with the other.

Thanos then uses the Time Stone to reverse the last few seconds locally, restoring Vision intact, and rips the Stone out of his skull while he's alive and conscious.

Wanda watches her partner die twice inside a minute. It is the cruellest beat in the franchise, and it is why WandaVision makes sense.

On Titan the team nearly wins — Mantis has him sedated, Parker is pulling the Gauntlet off — until Quill learns Gamora is dead and punches him awake. Thanos then drives a piece of Stark's own armour through his abdomen and holds him there. Strange, who spent the film insisting he'd let both Stark and Parker die first, hands over the Stone.

He sees those futures through the Time Stone itself, using it to view 14,000,605 outcomes.

His line to Stark in Endgame — "if I told you what happened, it wouldn't happen" — is the confirmation that everything after was deliberate.

Thanos is a Titan — an Eternal from the moon Titan.

The MCU has pointedly never connected him to Arishem's Eternals despite the shared name; the Eternals film avoids the question. His strength is native to his species and further enhanced.

He is physically stronger than the Hulk, which the opening forty seconds demonstrate.

His intentions surface gradually — established as a warlord who "wants everything dead" in Guardians (2014), shown putting on the Gauntlet in Age of Ultron's post-credits (2015), and given the full philosophy here: Titan collapsed from overpopulation, he proposed killing half at random, was called insane, and watched the planet die. He now applies the solution universally and considers it mercy.

Strange looked forward through 14,000,605 possible futures and found exactly one where they win. Everything he does after that — including surrendering the Time Stone — is executing that one path.

Thanos snaps his fingers. Half of all life in the universe disintegrates. Among the dead: Bucky, Wanda, T'Challa, Groot, Drax, Mantis, Quill, Strange, Sam Wilson, Peter Parker, Hank Pym, Janet van Dyne, Hope van Dyne, Nick Fury, Maria Hill.

Thanos retires to a farm. He wins.