The Gameboy Final Fantasy games
You may have some RPGs on the GB that bear the Final Fantasy name. These are Squaresoft titles, but really aren't a part of the series.
They were given the FF name to sell more copies. These games actually belong to two different game series. Final Fantasy Adventure is the first Seiken Densetsu(known as Secret of Mana in the US) and FF Legend 1-3 are actually part of the Romancing Saga series.