This article is from the Final-Fantasy and other Square Soft Games FAQ, by email@example.com (Nick Zitzmann) with numerous contributions by others.
Long ago, the ancients built a gigantic Tower which linked many
different and unique worlds together for easy access. It is said that a
special Paradise exists on the top floor of the Tower, but oddly enough,
monsters have come out of the tower and the "main" worlds of the tower
have been sealed off by fiends, all under control of a creature named
Ashura. Now, there is another who has dared to brave the adventure,
destroy Ashura and claim the elusive and infamous (yet only fabled)
SaGa is very different from the regular Final Fantasy games - there are
no set characters and no occupations. Instead, you get to make up your
own party (see article 4.1). Humans must be manually upgraded using
various items the party acquires, mutants upgrade on their own and learn
up to four new spells on their own, and various monsters who gain powers
by eating the meat of other monsters.