What If...? (Season 1)

Skippable, and it is an anthology, so the sensible approach is to pick episodes rather than watch nine. Nothing in the films requires it, though one character introduced here recurs in Doctor Strange in the Multiverse of Madness and in later seasons.

The format is a single changed decision per episode, narrated by a cosmic observer. The quality varies enormously because the premises do: some are genuinely clever and some are a costume swap. The strongest are the Doctor Strange episode, which follows a man undoing the universe to save one person and is the darkest thing in Phase Four, and the zombie outbreak episode, which spun off its own series.

Most of the original cast return to voice their parts, with a few notable absences, and the animation is a cel-shaded style that reads as deliberately unreal. The series is at its weakest when it uses its freedom for fan service and at its best when it treats the alternate as a tragedy.

The finale assembles a team across universes and is the thinnest episode. Treat it as a short-story collection and read four of them.