Really playing Super Metroid for the first time, I'm surprised at how good it is. It doesn't feel like a 30 year old game.
It manages to guide the player so well through level design, but still always requires and rewards thorough exploration.
So you have to really engage with the world, and that in turn makes the atmosphere so much stronger. (+ the awesome music)
Such good design, it must have been mind-blowing for people who played it back in 94