Nobody talks about this one. A single song transforms a playground game into something that actually moves you, the melody does what the story can't, carrying weight that a kids' game has no right to hold. The OST isn't background noise propping up a narrative. It IS the narrative. If you've ever felt the pull of a great song that made a simple moment matter, this is what that looks like compressed into six minutes.
Oyama no Taishou is a single-episode music piece that sets the children's game King of the Hill to song. The whole release is built on that playground game, turning it into the subject of a musical adaptation.