Complex sentence: Unlike the other "Panzer Dragoon" games, which are rail shooters, "Panzer Dragoon Saga" is an RPG; the dragon's course is not "on rails", and can be moved in any direction.
Split into simpler sentences: Unlike the other "Panzer Dragoon" games, which are rail shooters, "Panzer Dragoon Saga" is an RPG. The movement of the player's dragon is not "on rails", and can be moved in any direction.