Recently found out about Everhood, and immediately got totally addicted to its soundtrack. I've never, ever watched a game video this long before (warning, video crammed with spoilers), but I couldn't stop coming back to watching/listening to this game's boss fights until I'd seen the entire set without realizing it. The stories told by the fights are also really good, like the bonus level where you face the devs, which is a big allegory for developing the game... and my favorite song out of the entire bunch, which you get as part of an uberboss fight triggered by going against the entire message the game is trying to express, in a homage/counterpoint to Undertale.

Of course, watching the videos of Everhood made it clear I would be so, so horrifically bad at the game that I've got no inclination to play it myself, but the fact that I've gotten a ton of entertainment out of it anyway is another sign it's a great game.