As a triumph of level design, as a gripping musical composition, and as a creation of eerie sci-fi atmosphere, Super Metroid is nothing short of a masterpiece.
The game picks up where the Game Boy installment, Metroid 2: The Return of Samus, left off. Samus Aran, the protagonist bounty hunter, is delivering a recovered Metroid (energy sucking alien) larva to scientists in order to study the dangerous species (after having exterminated most of them on their home planet of SR-388).
All seems well, until the research space station is attacked by Ripley, Samus's monstrous space pirate nemesis. Ripley takes off with the Metroid larva to the space pirate fortress of Zebes, where Samus did battle in the first Metroid on the NES. This necessitates a return to confront Ripley and the hideous Mother Brain in that fortress of evil once more, to prevent the power of the Metroids from being used by the pirates for nefarious means.
Super Metroid has a number of improvements over its predecessors in the franchise, first and foremost being the inclusion of an in-game map. The game shipped on the largest ever cartridge made at the time: 24 megabits. It certainly shows, as the graphics use every two-dimensional effect in the SNES's arsenal. Furthermore, the music is absolutely fantastic...at times creepy, at times upbeat, at times urgent, but always beautiful and impossible not to get stuck in one's head. Few titles have ever matched Super Metroid's overall presentation, with an epic opening that stands as an all-time best, and a twist surprise ending that manages to humanize a bloodthirsty alien.
But it's the gameplay that puts this title over the top into classic status. Super Metroid gradually and continually grants Samus power-ups (such as increased missles, power-bombs, the coveted Ice Beam and Wave Beams, the Varia suit) to give the intrepid bounty hunter the ability to defeat the ever more difficult bosses thrown her way. However...if you so choose, you can forego exploring for a majority of the power-ups in favor of attempting a "speed run" with a reduced arsenal. In fact, Super Metroid rewards this activity, reserving the very best ending (Samus in a bikini) for those players who can complete the game in under three hours (a very difficult task, both from a coordination and a weapons standpoint). Of course, conversely, a player can attempt a 100% completion rate on item pick-ups, resulting in a "Where's Waldo?"-like gathering mission to find every last missle canister and energy tank.
And finally, the Metroid franchise was one of the first to shatter the usual gaming paradigm of the damsel in distress by putting a strong female in the ass-kicking lead role. (The ending of the original Metroid shocked the player by revealing Samus's true gender.)
Super Metroid could easily be called the Super Nintendo's finest hour, and it remains one of the best pieces of software ever put to code.