Short answers, pulled from the story.
The Final Fantasy Legend is a 1989 role-playing video game developed and published by Square for the Game Boy. It was originally released in Japan in December 1989 as Makai Toushi Sa·Ga and in North America on the 30th of September 1990 under the Final Fantasy Legend name.
The Final Fantasy Legend is Square's first game to sell over one million copies. The Game Boy version shipped 1.37 million copies worldwide, including 1.15 million in Japan, as of March 2003.
Nobuo Uematsu composed all sixteen tracks for The Final Fantasy Legend. He worked with the Game Boy's limited sound hardware, which offered only three note types, and developed new waveforms rather than imitating earlier Final Fantasy music.
The Final Fantasy Legend is the first installment of the SaGa series, released in Japan as Makai Toushi Sa·Ga. Square renamed it for Western markets to tie into the Final Fantasy brand. The game introduced SaGa's signature mechanics, including the meat-based monster transformation system and weapon degradation.
Game Freak founder Satoshi Tajiri cited The Final Fantasy Legend as an influence on the Game Boy Pokemon series, stating it gave him the idea that the handheld system could handle more than action games.
After its original Game Boy release, the game was rereleased in North America by Sunsoft in 1998, ported to WonderSwan Color in Japan in March 2002, and made available for Japanese mobile phones in 2007 and 2008. In 2020 it appeared on Nintendo Switch as part of Collection of SaGa: Final Fantasy Legend, and ports to Android, iOS, and Microsoft Windows followed in 2021.