First Class
This is the one that made me love the Metroid games after being more ambivalent about them previously, thanks to various quality of life improvements, improved and evolved controls (8-way aiming! Toggleable equipment! Wall jumps!), a great map system but also all the other things fleshing out the experience in a more subtle and refined way like the environmental storytelling focus and improved sense of place. Plus the unnecessary but cool things like power bomb healing.
World design and atmosphere are top tier here with a memorable intro, distinct areas that are rewarding to explore, solid visuals that don't distract from the gameplay, interesting touches like the foreshadowing of Maridia, great overall pacing, creatures that seem more like they live in the world rather than being placed there to wait for and fight the player as well as neutral and friendly ones.
There are also some well done sci-fi horror elements in the boss introductions, the crashed ship, the intro leading up to the player being attacked on the planet, and a good sense of vulnerability and solitude throughout most of it with the former being contrasted by the near god form attained in the finale in a cool way.
Player movement (once you have all the upgrades and know advanced techniques), while there have been minor improvements for later games in an action game sense, is still rather flexible and satisfying, and gels perfectly with the aforementioned sci-fi horror aspect. You are in a super suit that grants you amazing abilities like space jump and shinesparking but this is not earth, gravity and friction are not the same and you are not the most adapted to this environment - the enemies are, as shown in their greater mobility. I've seen complaints about the wall jump but I think they did it just right considering the sequence breaking opportunities it provides; you feel like a champ when you start mastering it and breaking the intended path through the game. With it, bomb jumping, and (the unintended but easy to pull off and less glitchy than an out of bounds trick) mock ball you can make the game pretty much fully non-linear, and if you need more replay value there are various well made hacks and randomizer hacks to check out. Super Metroid is still my fave game in the platform adventure/metroidvania genre, and an all-time classic.
