Mystic Quest is one of the very few Final Fantasy games to never get a remake or re-release, and unfortunately there's a reason for that. The combat system switched to a different view more along the lines of Phantasy Star, and the story and characters were incredibly weak, mostly existing as vehicles for a never-ending string of monotonous battles.
Trudging through the constant onslaught of repetition becomes a serious chore that makes Mystic Quest hard to play for extended periods. Despite all that, I have to admit I still I have a soft spot in my heart for this red-headed stepchild of the FF series, mostly because of the many hours I put into it as a young 'un. And on the plus side, it's not Final Fantasy 13.