In the SNES golden era of gaming Squaresoft was dominant, and this was one of it's ilk
The graphics have a unique and un-blemishible level of style to them that simply dont run a high risk of getting outdated, with excellent character design art by Akira Toryama.
The music in this game was also up to expected Squaresoft qualities for the era, making a very omnipresent soundtrack that was both original and enjoyable.
The gameplay was very well done as well, with the combo system combined with the traditional RPG elements, it was an original game executed successfully to the point that it has made it the classic it is today. It's especially fortunate that the game has held up well due to it being made at the height and mastery of the primary 2d era.
The plot was also very well done, with multiple endings and alot of gloom to complement the happy moments it had a balanced and epic feel that make it great and memorable.