An Action-RPG series by Square Enix known as Mana in the US, which involves Mana being the lifeforce of the world, and the Mana Goddess, Mana Tree, and Sword of Mana as central figures in each storyline. Seiken Densetsu literally translates to "Holy Sword Legend," or Legend of the Holy Sword.
The series is as follows:
Final Fantasy Adventure--Seiken Densetsu (GB, 1991)
Secret of Mana--Seiken Densetsu 2 (SNES, 1993)
Seiken Densetsu 3 (Japan Only, SNES, 1995)
Legend of Mana--Seiken Densetsu: Legend of Mana (PS1, 2000)
Sword of Mana--Shin'yaku Seiken Densetsu (GBA, 2003)
World of Mana Compilation:
Children of Mana--Seiken Densetsu DS: Children of Mana (NDS, 2006)
Dawn of Mana--Seiken Densetsu 4 (PS2, TBA)
Seiken Densetsu: Final Fantasy Adventure (Mobile, 2006)
Seiken Densetsu owns Kingdom Hearts!
Known as the Mana series in America, this video game series began with Final Fantasy Adventure for the Game Boy in the early 90's, had two sequals on Super Famicom (only one made it to Super Nintendo), one on Playstation 1, and the original was recently remade for the Game Boy Advance.
I have an emulated and translated version of Seiken Densetsu III for SNES on my computer.